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Strands of hair caught on a barbed wire fence at a crime scene  GClark

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Hair was collected and is being ready to be exanimated for a case. - Lashundra M.

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(second slide)
-Lashundra M.

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CTE Gateway :: California Educators Together

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The California Educators Together platform is brought to you by a collaboration between the California Department of Education and the CDE Foundation.

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When collecting hairs they use tweezers or their hand, and they can also use clear tape to lift non-visible hair from a variety of surfaces.
-Lashundra M

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Home > 3. Evidence Collection > Hair and Fiber

The most common methods used to collect hair and fiber evidence include the following:

Visual collection. On some surfaces, hairs and fibers can be seen with the naked eye. Through use of clean forceps and paper (i.e., trace paper), the sample can be removed from the surface and placed into a clean piece of paper that can be folded and packaged in a paper envelope.

Tape lifting. Trace tapes are available for the collection of trace hair and fiber evidence. The tape is applied to the location of the suspected sample, removed and packaged.

Vacuuming. The area where the suspected samples are located is vacuumed and evidence is caught in a filtered trap attached to the vacuum. These samples are packaged in clean trace paper for submission to the laboratory. Vacuuming is the least desirable collection method because there is a risk of cross-contamination if the equipment is not properly cleaned between each use.

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Home > 3. Evidence Collection > Hair and Fiber The most common methods used to collect hair and fiber evidence include the following: Visual collection. On some surfaces, hairs and fibers can be seen with the naked eye.

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- Lashundra M.

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Hairs, Fibers, Crime, and Evidence | Office of Justice Programs

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- Lashundra M.

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The two men wrapped Elizabeth Ballard's body in plastic. They vacuumed and scrubbed the room in which she had been killed. They scoured the car trunk in which they transported her corpse to its shallow grave in the New Mexico desert.

They tried to cleanse the world of anything linking them to Ballard's death. A single dog hair thwarted them.

It belonged to Hercules, a reddish-brown pit bull mix owned by one of the men. The hair was found on one of Ballard's socks and helped send the pair to prison for her 1998 murder.

The hair was matched to Hercules in a laboratory in this Northern California college town, where scientists are pioneering the use of animal DNA as evidence in criminal cases. They are fingering suspects around the country with the genetic analysis of pet hair and blood, even feces and urine.

In some cases, Spot and Puff are providing evidence against their owners' killers. In others, they are convicting the owners themselves.

The blood of a Seattle dog was instrumental in convicting gang members who murdered the couple it lived with. Urine sprayed on a truck tire by an Iowa farm dog helped identify his owner's assailant. Bits of dog feces on a shoe implicated a suspect in the execution-style slayings of three Indiana carpenters.

Though genetic testing has played an integral role in wildlife forensics for more than a decade--linking game poachers and smugglers to their prey--law enforcement has begun to use animal DNA in criminal prosecutions only in the last few years. Still relatively rare, pet DNA evidence could become a valuable forensics tool, say criminal experts.

Specimens often wind up here, either in the UC Davis Veterinary Genetics Laboratory or the offices of scientist Joy Halverson. For now, these are among the few places in the country where authorities can go for pet DNA testing. The veterinary lab even performed work for Scotland Yard earlier this year, analyzing dog blood samples collected after a pub killing.

The ability to conduct animal DNA testing at a level sophisticated enough for criminal trial use is a product of two developments: the last decade's astounding advances in human gene-mapping techniques and the creation of genetic databases for various domesticated animal species.

"A lot of the technology is a fallout from the human genome project. We just applied that to animals," said Beth Wictum of the Davis veterinary genetics lab, which has developed animal DNA profiles for genetic screening and parentage verification of livestock and pets.

The first introduction of pet DNA evidence in a criminal court case is believed to have occurred in Canada in 1996, when prosecutors used cat hairs found on a bloodied jacket to link a Prince Edward Island man to the murder of his estranged wife.

The DNA match was made at the National Cancer Institute in Maryland, which has done extensive research in cat genetics for its work on human disease.

"It just so happened the [genetic markers] we developed for the cat map had forensic potential. We got enlisted in forensics," said cancer institute staff scientist Marilyn Menotti-Raymond, who, with colleague Stephen O'Brien, performed the cat hair analysis.

Their lab was too small to do ongoing criminal casework. But it did sign a $265,000 contract with the U.S. Department of Justice to develop a feline genetic database for forensic use. Menotti-Raymond is collecting DNA samples from the 37 pure cat breeds and expects eventually to move on to mixed breeds.

Genetic Profile of Species Required

To say with a high degree of probability that a tissue sample comes from a particular animal and not just any dog or cat requires a genetic profile of the species--basically a map of genetic variability within the species.

The UC Davis lab has genetically profiled nearly a dozen domesticated species for pedigree work, so when it makes a DNA fingerprint of an individual animal, the lab can say how rare that particular sequence of genetic markers is.

If the lab matches DNA from samples, it can say, for instance, that there is a 2-in-a-billion chance or less of such a match occurring--roughly the same odds used in human DNA matches.

"Anybody can DNA-type an animal, but unless you know how frequently the markers appear, it's not going to be informative," said Wictum, forensics case manager at the UC Davis lab.

The lab's forensic testing, which has involved homicides, stolen livestock, dog maulings and animal abuse, is a tiny fraction of its workload--one or two cases a month compared with more than 3,000 samples a week processed to verify animal parentage or screen for genetic disease. But the criminal cases stand out.

"You see really bizarre types of people and what they do to each other and to animals. It can be sad," said Teri Kun, a research associate who devotes about half her time to forensic work. "But when it matches up and they've got the right person, it's nice to be a part of that."

The work can be painstaking, involving repeated testing of minute quantities of concentrated material.

"I really hate to give up on a case. I'll keep going back and going back," said Wictum, who likes to replicate results several times before reporting them.

One of the lab's more challenging samples came from Indiana, where St. Joseph County prosecutors had a suspect's shoe and a footprint from the scene of a triple homicide about 80 miles east of Chicago. Three carpenters working at an upscale residence had been found bound and shot in the head, the apparent victims of burglars.

The footprint had been lifted from dog feces on a sidewalk leading from the carpenters' bodies. A shoe belonging to the alleged triggerman had bits of feces clinging to it. Authorities wanted to see if they matched the sidewalk print.

They did--something that gives prosecutor Scott Duerring metaphorical, as well as professional, satisfaction.

"If I can use this kind of evidence to eliminate a person like this from our society, it fits," said Duerring, who is preparing for trial in the case.

'An All-or-Nothing, One-Time Shot'

The shoe specimen was tiny, making the first tests critical.

"In this case it was an all-or-nothing, one-time shot, and we got results, very beautiful results," Kun said.

In the Iowa case, investigators sent the veterinary lab swabs of dog urine. They had been taken from the tire of a pickup driven by a man suspected in a 1999 attempted sexual assault at an isolated farm in the northeastern part of the state.

The victim, who fought off her assailant as he tried to drag her into the truck, left fingerprints on the vehicle. But when he was picked up based on her description, the woman could not positively identify either the truck or the driver.

Doug Strike, then chief deputy in the Chickasaw County sheriff's office, was looking over the pickup with an investigator when they noticed a stain on the tire.

"We knew there was a farm dog on the place, and we thought maybe the dog peed on the tire," remembered Strike, who is now police chief in Iowa Falls. "I went out and talked to the lady, and she said, 'Yeah, the dog was in the yard.' "

Strike swabbed the mouth of the dog, Rover. A detective took swipes from the tire. The genetics lab matched the specimens, and the suspect pleaded guilty to an assault charge.

Joy Halverson's work has also played a key role in various criminal convictions.

The UC Davis veterinary school graduate has spent 16 years working in animal genetics, first in a research job at the university and then with private companies.

In 1989 she founded Zoogen Inc., which used DNA typing to determine the gender of exotic birds, something that previously required surgery. The company, which later merged with bigger players in the genetics field, branched into parentage testing for livestock and pets.

By the late 1990s, law enforcement was calling Halverson's Davis office about criminal cases, taking her into a world far removed from small-town academia.

"I live a pretty sheltered academic community life," said Halverson, who is married to a UC Davis genetics professor and has two college-age daughters, two dogs and two cats. "I'm just intrigued by this."

This fall she left PE AgGen, where she was a senior scientist, to once again launch her own operation. Her bread and butter will be bird gender testing. But under the name QuestGen Forensics, she is also doing animal DNA typing in criminal and insurance liability cases.

One of the cases that drew her into forensics work was the Ballard murder.

Ballard had been Christopher Faviel's girlfriend during a break in his relationship with Charles Martinez, a transvestite who went by the name of Eva. When Faviel and Martinez got back together, Ballard continued to see Faviel and publicly harassed Martinez for his cross-dressing.

One night when she showed up drunk at the men's house, Martinez hit her over the head with a thermal coffee carafe and then strangled her with Faviel's help, according to prosecutor Canon Stevens.

The men told friends what happened. Word got to the police. When Ballard's body was discovered a month later, her hair had been scattered over the desert by coyotes, making it difficult to collect trace evidence. But the state criminal lab did find a few animal hairs on the socks Ballard was wearing.

One hair had a root. Lab analyst Philip Aviles thought it might be tested for DNA. He just didn't know where. He searched the Internet and came across a Seattle homicide case involving dog DNA.

That led to Halverson, who had analyzed the Seattle canine evidence. Via Federal Express, she was sent a DNA extraction from the hair root and a blood sample from Hercules, Martinez's dog. The hair and blood matched, placing Ballard in Martinez and Faviel's home, despite their insistence to police that she had never been there.

Halverson had made her first courtroom appearance earlier that year, when she testified in the Seattle case. Two men were on trial in a double homicide.

"Some," said prosecutor Timothy Bradshaw, "would call it a triple homicide."

A young couple had been shot to death in their South Park house by intruders searching for drugs and money. The couple's dog Chief, a Labrador-pit bull mix popular with neighborhood children, was also shot. He died 30 hours later in surgery. When police arrested two suspects in the December 1996 slayings, they found blood on the arm of a leather jacket belonging to one of them.

Evidence Seen as Important to Case

The blood was sent to an East Coast lab, but test results indicated that it was not human. Bradshaw, senior prosecuting attorney for King County, said he and detectives remembered the two bloody wounds Chief had sustained and decided to try animal DNA testing. Through a national kennel club they found Halverson, who matched the jacket blood to a sample taken from Chief during surgery.

Though there was other trial testimony linking the men to the killings, Bradshaw said Chief's DNA evidence played an important role in their murder convictions.

"We argued that one of the ironies in the case was that the victim who couldn't speak wound up providing the most eloquent evidence," Bradshaw said. "He ended up serving his roommates quite well."

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The two men wrapped Elizabeth Ballard's body in plastic. They vacuumed and scrubbed the room in which she had been killed. They scoured the car trunk in which they transported her corpse to its shallow grave in the New Mexico desert. They tried to cleanse the world of anything linking them to Ballard's death.

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-Zylus Breeden

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/ KCAL News

RUBIDOUX (CBS 2) - The case is worthy of any "Cold Case" story shown on TV. Riverside County sheriff's homicide detectives announced Tuesday that they have solved the 1977 murder of a Rubidoux bartender.

Hair found clenched in the victim's hand was recently sent to a private laboratory in Texas for DNA testing, a sheriff's sergeant said.

The DNA test showed that the hair belonged to Frank Wright, who died in 2002 from complications related to alcohol abuse, said Sgt. Scott Brown of the Riverside County sheriff's Central Homicide Unit.

James Anagnos, who was known as "Jimmy the Greek," was found dead Oct. 18, 1977 inside his bar at closing time, Brown said.

Anagnos was stabbed 20 times with a steak knife and had been hit four times in the head with a blunt object, Brown said, adding that the cause of death was from injuries to his head.

The hair was found clenched in Anagnos hand, and was believed to have come from the suspect, but the laboratory at the time was not able to match the hair samples to Wright who was 50 at the time of his death.

Wright was identified as a suspect when detectives learned he was involved in an argument with Anagnos about an hour before the bar's closing, according to Brown.

There were no independent witnesses to the attack, so the District Attorney's Office did not file charges against Wright, Brown said.

The hair was sent earlier this year to Orchid Cellmark, a private lab in Texas, for testing, he said.

The DNA test confirmed the hair found in Anagnos' hand belonged to Wright, according to Brown.

This was the third case solved by the Cold Case Unit since being awarded a grant by the National Institute of Justice.

The sheriff's Cold Case Unit is examining more than 70 unsolved cases that may have DNA evidence, Brown said.
©2010 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Wire services contributed to this report.)

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KCAL News RUBIDOUX (CBS 2) - The case is worthy of any "Cold Case" story shown on TV. Riverside County sheriff's homicide detectives announced Tuesday that they have solved the 1977 murder of a Rubidoux bartender. Hair found clenched in the victim's hand was recently sent to a private laboratory in Texas for DNA testing, a sheriff's sergeant said.

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Trace tapes are available for the collection of trace hair and fiber evidence. The tape is applied to the location of the suspected sample, removed, and packaged.
-Zylus Breeden

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Place the hair in an evidence or pharmacy fold then place the fold in an envelope and properly label.
-Zylus Breeden

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Hair being tested
-Zylus Breeden

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ARBIDAR Company- Natural Fiber Collection

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ARBIDAR Company- Natural Fiber Collection

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-Zylus Breeden

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ATF Trace Evidence Unit Reference Collections

Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF)

Collections of various trace evidence samples; automotive paint pigments, human hair, animal hair, fibers, black spray paint, silicone adhesive, electrical tape, and duct tape. Collections include various automotive paint pigments, human hair, animal hair, fibers (hundreds), black spray paints (~10), silicone adhesives (30-50), electrical tape (30-40), and duct tape (20-30).

Collection can be accessed by emailing POC.

Some samples (i.e. human and animal hair) are steadily accumulated. Others (i.e. black spray paint, silicone adhesives) are collected for a specific case. Samples are collected from various sources, including volunteers, casework, and commercial vendors.

Physical samples.

Leonora Bender
Bureau of Alcohol, Tobacco, Firearms,
and Explosives (ATF)
202.648.6146

Digital Automotive Image System (DAIS)

Automobile Identification

Federal Bureau of Investigations (FBI) -- Digital Evidence Laboratory

A digital system, which fits entirely on one DVD, with photos and data of motor vehicles commercially manufactured in the last twenty years. Used in image analysis to provide opinions as to whether a car in a photo could be a particular make, model, or year car. Collection of images of make, model and year of cars. Includes front, side, and rear photos of motor vehicles and accompanying data. The software can generate "Be On the Lookout"-type posters and produce photo lineups. DAIS contains thousands of records.

User must request a DVD from the FBI. Database can then be downloaded from DVD and installed on an unlimited number of computers. The data is searchable by vehicle category, body style, number of doors, and other characteristics. CDs are available up request to law enforcement only.

Images are obtained per contract with Southwest Research Institute through TSWG.

Digital records.

EPA NEIC Asbestos Collection

Asbestos, Silicate Mineral

Private Collection, Owner works for EPA NEIC

Self-maintained, private collection of asbestos samples. Owner is willing and has provided samples to requesting parties on occasion. The collection contains 20-40 asbestos samples collected from mines in North America (Vermont, Quebec, North Carolina, Arizona), rockshops, and bookshops.

Contact the POC/Owner. Physical samples are available for some, but not all, of the collection's specimens. Currently only used internally and for educational purposes in court. Any outsider with a legetimate cause can request access.

Samples collected from caves, or purchases in rockshops and bookshops by the collection owner.

Physical samples.

Peggy Forney,
Collection Owner
National Enforcement
Investigations Center,
EPAC
Chemist
303.462.9110

European Collection of Automotive Paints (EUCAP)

Paint, Automobile Identification

The French Police Lab maintains the database; data analysis is performed by the Federal Criminal Police Force of Germany (BKA).

A searchable collection of paint samples removed from primarily salvage vehicles by law enforcement laboratory participants throughout Europe. Paint samples collected by European Law Enforcement Agencies.

The database can be accessed via the internet via a secure ID and password assigned by the French Police Lab.

FBI Lab - Fiber Library

Fibers

Federal Bureau of Investigations (FBI) -- FBI Laboratory

Database of FTIR spectra of textile fibers used to identify fiber types. Database includes 86 records. Each record includes FTIR spectra. Physical samples of fibers are also held.

Library is stored in FBI's version of the OMNIC library search software (Thermo Fisher Scientific Inc.). Outside agencies can request FBI Trace Evidence staff to carry out analysis by contacting POC. No cost to access; outside labs and agencies can submit requests to FBI.

Most of the fiber samples were obtained from Collaborative Testing Services (a commercial company).

Digital records and physical samples.

FBI Lab - Forensic Automobile Carpet Database (FACD)

Fibers, Automobile Identification

Federal Bureau of Investigations (FBI) -- FBI Laboratory

A collection of carpet fibers removed from vehicles. Fibers are entered into a centralized searchable database that is used to provide investigative make/model/year information. Collection includes about 800 samples of known automobile carpet fibers. Records include microscopic characteristics including cross-section, diameter, color as seen through microscope, IR microscopy, microspectrometry.

Sample is first analyzed and a search is carried out using a Microsoft Access database. The sample is then compared with physical samples of possible matches. Outside law enforcement agencies will be able to submit evidence for analysis by the FBI. No cost to access; outside labs and agencies can submit requests to FBI.

Fibers come from personally-owned vehicles, manufactures, and junkyards.

Digital records and physical samples.

Stephen Shaw
Federal Bureau
of Investigations,
FBI Laboratory
703.632.7706 stephen.shaw@
ic.fbi.gov

International Forensic Automotive Paint Data Query (PDQ)

Paint, Automobile Identification

Royal Canadian Mounted Police (RCMP)-- Forensic Laboratory Services

The International Forensic Automotive Paint Data Query (PDQ) database is a centralized, searchable database of chemical and color information of original automotive paints. Search results provide make/model/year information. PDQ contains foreign and domestic automotive paint samples from ~13,000 vehicles and ~50,000 layers of paint. Most paint samples consist of four layers typically used for an automotive job. Contains majority of post-1973 vehicles marketed in the US.

Access is granted through a program updated and released by RCMP annually through a CD release. Law enforcement agencies interested in PDQ who are not already members can contact PDQ directly by email. Partnering agencies also have access to physical samples by request. Use of the PDQ is for bona fide law enforcement agencies only that perform forensic paint examinations as part of criminal investigations. "Payment" for access to the database is the submission of 60 samples to PDQ each year. In addition, users must sign a non-disclosure agreement.

Every accessing institution must submit 60 paint samples per year, these usually come from vehicles at body shops or junk yards or manufacturers. Samples are also collected directly from some automotive companies.

Samples are analyzed for their identifying chemical properties, and this information is stored digitally. Physical samples are available by request (see more information).

Email PDQ:

Mark Sandercock
Manager, Trace Evidence
Operations Support
National Centre for
Forensic Services -
AlbertaRoyal Canadian
Mounted Police
780.451.7418
mark.
sandercock@
rcmp-grc.gc.ca

Diana Wright
Federal Bureau
of Investigations,
FBI Laboratory
703.632.7418

Locke Scientific - GRIM Glass Standards

Glass

Locke Scientific (commercial)

Glass standards for GRIM.

Standards can be purchased for use in the laboratory.

Physical samples.

Susan Gross
Minnesota BCA
Chemistry Supervisor
651.793.2900
sue.t.gross@
state.mn.us

McCrone Microscopes & Accessories - Slide Sets

Reference Materials/ Standards

McCrone Microscopes & Accessories (commercial)

Microscope company stocks a number of slide sets that serve as reference collections for forensic analysis. Sets include a paint pigment set, particle set, fiber reference sets, white powder set, and an asbestos reference set. Paint Pigment Set - 50 samplesFiber Reference Set - 100 samplesAsbestos Reference Set - 25 samples; includes materials that contain asbestosParticle Reference Set - 100 samplesWhite Powder Set - 25 samples

Standard reference materials and slide sets can be searched and purchased on the website. Paint Pigment Set - $325.00; Fiber Reference Set - $725.00; Asbestos Reference Set - $450.00; Particle Reference Set - $725.00; White Powder Set - $300.00

Samples in each slide set are selected by based on most commonly seen specimen for each category.

Physical samples purchased from an online catalogue.

MicroTrace - SRM Collections

Reference Materials/ Standards

MicroTrace Scientific (commercial)

Company that sells reference material collections and slide sets. Reference materials include forensic fiber reference collection, natural fiber collection, hair and fur collection, forensic mineral analysis slide set, and automotive pigment reference collection. Reference Collections- Fiber Reference Collection: 200 traceable, authenticated synthetic fibers- The Arbidar Animal Hair and Fur Collection: 80 animal hair samples from around the world representing 49 genera- The Arbidar Natural Fiber Collection:80 samples representing a wide variety of natural fibers including vegetable fibers, animal fur fibers used in textiles, silks, and papersSlide Reference Collections:- Forensic Mineral Reference Collection: approximately 40 slides of minerals that are forensically significant- Automotive Pigment Reference Collection: approximately 40 slides of paint pigments from automotive manufacturers

Standard reference materials can be searched and purchased on the website. Cost varies by product; legitimate forensic laboratories can purchase.

N/A

Physical samples are available for purchase through the online catalog.

Microtrace LLC
790 Fletcher Drive
Suite 106
Elgin, IL 60123-4755
847.742.9909

National Automotive Paint File (NAPF)

Paint, Automobile Identification

Federal Bureau of Investigations (FBI) -- FBI Laboratory

A physical collection of automotive paint panels acquired and maintained by the FBI's Chemistry Unit for use in casework. NAPF is a physical collection of paint color standards and/or full system paint panels (as a vehicle would be painted, not just the top coats). It contains approximately 14,000 automotive paint panels.

NAPF is used in an investigation to make a physical comparison of evidentiary paint chips to known paint colors to aid in identifying possible vehicle makes and models in hit-and-run investigations. The FBI Lab may be able to provide small samples of specific vehicle colors to other law enforcement agencies if that agency has some knowledge of the specific color or model they are seeking.

Automotive manufacturers provide these physical samples free of charge to the FBI Lab for all vehicles available for purchase in North America. This does not include commercial vehicles such as trucks, buses, motorcycles or RVs.

NAPF is not a database; physical samples are available.

Diana Wright
Federal Bureau
of Investigations,
FBI Laboratory
703.632.7418

National Forensic Tape File (NFTF)

Tape

Federal Bureau of Investigations (FBI) -- FBI Laboratory

The National Forensic Tape File is used for determining the manufacturer and/or product for duct tape sourcing requests and is also a repository for samples used in the FBI duct tape and electrical tape discrimination studies. ~500 tape samples stored in-house in plastic bags and plastic bins in a storage cabinet. Physical properties and/or chemical composition can be searched in SLICE software to determine potential manufacturer/product candidates, and then those candidates can be pulled out of NFTF for a direct comparison to the unknown sample.

The Florida Department of Law Enforcement (FDLE) and FBI both use SLICE software to interact with digital tape records. - FDLE and FBI are willing to share their digital records with other forensic scientists that have SLICE and are willing to share/exchange samples.- For a laboratory without the SLICE software, the FBI can conduct the analysis for them as long as it adheres to the case acceptance policy. Case Acceptance Policy: Usually if it's a case that has FBI jurisdiction, they will accept it and perform the analysis. If the lab has its own capabilities, then it must do the analysis itself (but FBI and FDLE will share/exchange data and samples).

Manufacturers provide rolls free of charge (majority of samples) or samples are purchased. A new roll is assigned a sequential number, put into a storage cabinet, its paperwork is filed, and then it is analyzed and data is put into SLICE.

Digital records can be shared through the SLICE software. Physical samples are maintained in-house.

Andria Mehltretter
Federal Bureau
of Investigations,
FBI Laboratory
703.632.7415
andria.
mehltretter@
ic.fbi.gov

Polyethylene Repository & Information Database for Evdience (PRIDE)

Plastic Bags

Federal Bureau of Investigations (FBI) -- FBI Laboratory

Repository of polyethylene reference samples. Examples include trash bags and sandwich bags. Database can be used to determine the possible manufacturer of a bag used at a crime scene. Collection includes approximately 1,000 samples of polyethylene bags.

There is a standalone system at the FBI Laboratory Questioned Documents Unit. The QDU will search the system to fulfill outside requests. Outside agencies submit the questioned specimen for QDU to do analysis. No cost to access; outside law enforcement agencies can submit requests to the FBI.

Samples were obtained as part of a research project for development of the database. Additional samples are provided by the program manager. Submitted samples are not added to PRIDE because manufacturer information is unknown.

Digital records and physical samples.

Meg McHenrymarguerite.mchenry [at] ic.fbi.gov (marguerite.
Federal Bureau
of Investigations,
FBI Laboratory
703.632.7283

mchenry@
ic.fbi.gov)

Contacts if agencies have questions:

FBI Questioned
Documents Unit:
703.632.8444

FBI Evidence Control: 703.632.8360

Powder Diffraction File (PDF)

Powders

International Center for Diffraction Data (ICDD)

Database of powder diffraction data for the identification of crystalline materials. The database can be purchased in different versions. Collection includes 715,953 total records, broken down into numerous libraries that the user can purchase depending on user needs (basic version, advanced version, and mineral and organics add-ons). Diffraction, crystallographic, and bibliographic data are kept on each data set. Select physical properties are also kept.

PDF can be purchased as a standalone version on user's PC (depending on version). User must first purchase a license (1 year for advanced version, 5 years for basic version). For sales information, call the number listed or visit the website. Pricing information for various packages appears on the brochure. Product may be purchased after agreeing to the licensing terms.

The following institutions are collaborative partners on PDF:- International Center for Diffraction Data (ICDD); Newtown Square, PA- Cambridge Crystallographic Data Centre (CCDC); Cambridge, UK, Cambridge Structural Database (CSD)- National Institute of Standards and Technology (NIST); Gaithersburg, MD- Fachinformationszentrum Karlsruhe (FIZ); Karlsruhe, Germany, Crystal Structure Database (ICSD)- Material Phases Data System (MPDS); Vitznau, Switzerland, Linus Pauling File (LPF)

Digital records.

TireGuides, Inc. - Tread Design Guide

Impressions

Tire Guides, Inc. (commercial)

Database of tire tread designs utilized to provide investigative lead information on possible make and model for unknown impressions. The Tread Design Guide shows tread patterns for all types of tires sold in the U.S.*A comprehensive Visual Identification of all types of Tire Tread Pattern Designs.*Covers Passenger, Light Truck and Medium Truck vehicles.*Includes Off-Road and Agricultural Tread Patterns.*Also covers Motorcycle and retread tire tread designs.*Provides information on how to read a tire sidewall and on the different Tire Sizing Systems.*Gives detailed information on Speed-Rating and Load Indexes as well as lug nut torque and tightening sequences.*Back Issues available.

The individual guides can be purchased as a hardcopy book. A computerized version is also available. Contact Tire Guides Inc. by phone or through the URL. Price Quantity (from website)$28.00 1 - 4 $27.00 5 - 9 $25.00 10 - 24 $24.00 25 - 99

Tread patterns and other information compiled for tires sold in the U.S..

Digital records.

Tire Guides Inc. -
Tire Information Center
1101 South Rogers Circle
Ste 6
Boca Raton, FL 33487-2748 561.997.9229
tireinfo@
tireguides.com

TSWG Sponsored FIU Glass Database

Glass, Elemental Analysis

Florida International University, sponsored by the Technical Support Working Group

The database assesses the relative frequency that two glass samples from different sources would have the same elemental profile. The purpose of this database is to provide glass examiners a view of the frequency of occurrence of elemental composition for ~700 different glass samples originating from different sources. The database contains elemental analysis data for 12 elements for ~ 700 glass samples from manufacturers, distributors, and vehicle junkyards. Samples include: containers, float, headlamp, and vehicle glasses.

The database is not designed to be searched for casework in the way that other forensic databases (i.e. PDQ) but rather, it is to be used by researchers to estimate the probability of a random occurrence of elemental composition for different glass sources. Two plasma mass spectrometers are used to perform an elemental analysis of glass. Freely available to agencies and researchers with a reasonable cause.

Samples are collected from manufacturers, distributors, and vehicle junkyards. The data was collected from a single laboratory (FIU) as part of a research project.

Digital data records.

Dr. Jose Almirall, Professor
Department of Chemistry
and Biochemistry,
Florida International
University
305.348.3917

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ATF Trace Evidence Unit Reference Collections Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) Collections of various trace evidence samples; automotive paint pigments, human hair, animal hair, fibers, black spray paint, silicone adhesive, electrical tape, and duct tape.

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Hair is place in a Ziploc bag or bag after being picked up by a tweezer and put carefully into a bag .

vikira johnson

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Hairs are among the most commonly transferred trace evidence. They can be of considerable evidentiary value in linking individuals to crime scenes.

To collect hairs from a substrate, use the following procedure:

1. To collect visible hairs, use properly cleaned or disposable tweezers and carefully pick the hair off the substrate. Take care not to crush or break the hair when removing it. Place the recovered hair on a clean sheet of paper or Post-it® note (Post-it notes are useful for collecting hairs as the hairs are lightly held by the adhesive), taking care not to crease the hair in the fold. Place the folded paper into a properly labeled envelope (case number, date, exhibit number, a brief description, and your name).

2. Other ways of collecting questioned hairs (particularly if the hairs are not visible) from surfaces can be by tape-lifting or vacuuming.

1. To tape-lift an item, using clear packing or book tape, make a tape lifter by wrapping the tape back on itself around the tape roll, sticky side out. Roll the tape on the item until you have covered the entire object. If the tape gets too full of debris, use a second piece of tape. Cut the tape off of the roll and lay it, sticky side down, on a clean piece of clear plastic or sheet protector. The sheet protector or plastic sheet can be placed in a properly labeled envelope or container.

2. To vacuum an item, obtain a filter unit (which can be obtained from evidence collection suppliers) that attaches onto the nozzle of a vacuum hose. Proceed to vacuum the item and, when complete, preserve the filter (with the trace evidence on it) in an appropriate and properly labeled container.

​

If an item will also be examined for ignitable liquid residue, please consult the laboratory for the proper collection procedure. Items should not be air-dried or packaged in an air-permeable container if they will be examined for ignitable liquid residue.

​

Head and pubic hairs are generally the only human hairs that can be compared to known hairs. However, beard hairs may be suitable for comparison (check with your laboratory). When collecting known hairs for comparison, it is recommended that 25 pulled hairs and 25 combed/naturally shed hairs from various areas of the head (and beard, if present) or pubic region be collected.

To collect pulled hairs, be sure to wear new, unused, clean latex or nitrile gloves and pull 25 hairs (or have the suspect or person of interest do it themselves) from various areas of the scalp or pubic region. Place these in an evidence or pharmacy fold, place the fold in an envelope and properly label.

To collect combed or naturally shed hairs, you or the suspect (or person of interest) should take a clean, unused comb and comb their hair over a piece of clean paper. Fold the paper and the comb together and place it in a properly labeled envelope.

A buccal swab from the suspect or person of interest should also be submitted.

Some laboratories may also perform comparisons on animal hairs (check with your laboratory).

​

Laboratory testing of hair:

​

Source:

Crime Scene and Evidence Collection Handbook. Bureau of Alcohol, Tobacco, Firearms and Explosives, 2005.

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Hairs are among the most commonly transferred trace evidence. They can be of considerable evidentiary value in linking individuals to crime scenes. To collect hairs from a substrate, use the following procedure: To collect visible hairs, use properly cleaned or disposable tweezers and carefully pick the hair off the substrate.

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Hair being put into database and different categories .

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Hair is a common type of evidence submitted to the trace section for analysis. On average, humans shed approximately 100 head hairs per day. Because we are continuously shedding hairs, forensic analysis of hairs is beneficial to the establishment of associations between individuals, a person and an environment, etc. (Example: a questioned hair from a victim's jeans is examined and found to be consistent with the suspect's hair. This examination has provided evidence that an association may have occurred between the suspect and the victim).

A hair is a fibrous outgrowth from the skin of mammals and consists of three anatomical regions, the cuticle, medulla and cortex. Characteristics within these regions are used to determine whether the hair is human or animal, racial origin and body area. A microscopic hair examination can also determine if a hair was forcibly removed, artificially treated or diseased. A comparison microscope can be used to compare a questioned hair to a known hair sample in order to determine if the hairs are similar and if they could have come from a common source.

A questioned hair and known hair sample are viewed, side-by-side, using a comparison microscope in order to determine if they have similar characteristics.

Questioned hair Known hair Comparison Microscope

Hair suitability for DNA examinations

Nuclear DNA analysis can be done on human hairs. The trace section assists the DNA section by screening hairs and determining their suitability for DNA testing. A microscope is used to examine the root end of the hairs, in order to determine if they are suitable. The hair in photo 1 is suitable for nuclear DNA analysis and the hair in photo 2 is not suitable.

Photo 1 Photo 2

If a hair is deemed not suitable for nuclear DNA analysis (ex. no root present or no tissue is attached), it can be sent for mitochondrial DNA testing. A root does not have to present in order for a hair to be suitable for mitochondrial DNA testing.

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Hair is a common type of evidence submitted to the trace section for analysis. On average, humans shed approximately 100 head hairs per day. Because we are continuously shedding hairs, forensic analysis of hairs is beneficial to the establishment of associations between individuals, a person and an environment, etc.

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When collecting hairs they use tweezers or their hand, and they can also use clear tape to lift non-visible hair from a variety of surfaces.
vikira johnson

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Hairs are among the most commonly transferred trace evidence. They can be of considerable evidentiary value in linking individuals to crime scenes.

To collect hairs from a substrate, use the following procedure:

1. To collect visible hairs, use properly cleaned or disposable tweezers and carefully pick the hair off the substrate. Take care not to crush or break the hair when removing it. Place the recovered hair on a clean sheet of paper or Post-it® note (Post-it notes are useful for collecting hairs as the hairs are lightly held by the adhesive), taking care not to crease the hair in the fold. Place the folded paper into a properly labeled envelope (case number, date, exhibit number, a brief description, and your name).

2. Other ways of collecting questioned hairs (particularly if the hairs are not visible) from surfaces can be by tape-lifting or vacuuming.

1. To tape-lift an item, using clear packing or book tape, make a tape lifter by wrapping the tape back on itself around the tape roll, sticky side out. Roll the tape on the item until you have covered the entire object. If the tape gets too full of debris, use a second piece of tape. Cut the tape off of the roll and lay it, sticky side down, on a clean piece of clear plastic or sheet protector. The sheet protector or plastic sheet can be placed in a properly labeled envelope or container.

2. To vacuum an item, obtain a filter unit (which can be obtained from evidence collection suppliers) that attaches onto the nozzle of a vacuum hose. Proceed to vacuum the item and, when complete, preserve the filter (with the trace evidence on it) in an appropriate and properly labeled container.

​

If an item will also be examined for ignitable liquid residue, please consult the laboratory for the proper collection procedure. Items should not be air-dried or packaged in an air-permeable container if they will be examined for ignitable liquid residue.

​

Head and pubic hairs are generally the only human hairs that can be compared to known hairs. However, beard hairs may be suitable for comparison (check with your laboratory). When collecting known hairs for comparison, it is recommended that 25 pulled hairs and 25 combed/naturally shed hairs from various areas of the head (and beard, if present) or pubic region be collected.

To collect pulled hairs, be sure to wear new, unused, clean latex or nitrile gloves and pull 25 hairs (or have the suspect or person of interest do it themselves) from various areas of the scalp or pubic region. Place these in an evidence or pharmacy fold, place the fold in an envelope and properly label.

To collect combed or naturally shed hairs, you or the suspect (or person of interest) should take a clean, unused comb and comb their hair over a piece of clean paper. Fold the paper and the comb together and place it in a properly labeled envelope.

A buccal swab from the suspect or person of interest should also be submitted.

Some laboratories may also perform comparisons on animal hairs (check with your laboratory).

​

Laboratory testing of hair:

​

Source:

Crime Scene and Evidence Collection Handbook. Bureau of Alcohol, Tobacco, Firearms and Explosives, 2005.

# data[].attributes.attachment_link.description
Hairs are among the most commonly transferred trace evidence. They can be of considerable evidentiary value in linking individuals to crime scenes. To collect hairs from a substrate, use the following procedure: To collect visible hairs, use properly cleaned or disposable tweezers and carefully pick the hair off the substrate.

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Vikira johnson

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/ KCAL News

RUBIDOUX (CBS 2) - The case is worthy of any "Cold Case" story shown on TV. Riverside County sheriff's homicide detectives announced Tuesday that they have solved the 1977 murder of a Rubidoux bartender.

Hair found clenched in the victim's hand was recently sent to a private laboratory in Texas for DNA testing, a sheriff's sergeant said.

The DNA test showed that the hair belonged to Frank Wright, who died in 2002 from complications related to alcohol abuse, said Sgt. Scott Brown of the Riverside County sheriff's Central Homicide Unit.

James Anagnos, who was known as "Jimmy the Greek," was found dead Oct. 18, 1977 inside his bar at closing time, Brown said.

Anagnos was stabbed 20 times with a steak knife and had been hit four times in the head with a blunt object, Brown said, adding that the cause of death was from injuries to his head.

The hair was found clenched in Anagnos hand, and was believed to have come from the suspect, but the laboratory at the time was not able to match the hair samples to Wright who was 50 at the time of his death.

Wright was identified as a suspect when detectives learned he was involved in an argument with Anagnos about an hour before the bar's closing, according to Brown.

There were no independent witnesses to the attack, so the District Attorney's Office did not file charges against Wright, Brown said.

The hair was sent earlier this year to Orchid Cellmark, a private lab in Texas, for testing, he said.

The DNA test confirmed the hair found in Anagnos' hand belonged to Wright, according to Brown.

This was the third case solved by the Cold Case Unit since being awarded a grant by the National Institute of Justice.

The sheriff's Cold Case Unit is examining more than 70 unsolved cases that may have DNA evidence, Brown said.
©2010 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Wire services contributed to this report.)

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KCAL News RUBIDOUX (CBS 2) - The case is worthy of any "Cold Case" story shown on TV. Riverside County sheriff's homicide detectives announced Tuesday that they have solved the 1977 murder of a Rubidoux bartender. Hair found clenched in the victim's hand was recently sent to a private laboratory in Texas for DNA testing, a sheriff's sergeant said.

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vikira johnson

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Hairs, Fibers, Crime, and Evidence, Part 1, by Deedrick (Forensic Science Communications, July 2000)

July 2000 - Volume 2 - Number 3

Part 1: Hair Evidence
Unit Chief
Trace Evidence Unit
Federal Bureau of Investigation
Washington, DC

Hair Evidence | Hair Microscopy | Hair Anatomy and Growth |
Animal Hairs | Human Hairs | Body Area Determination | Racial Determination |
Age and Sex | Treatment and Removal | Biological or Environmental Alteration | Conclusions Significance of Hair Evidence
Hair Evidence
Hairs, which are composed primarily of the protein keratin, can be defined as slender outgrowths of the skin of mammals. Each species of animal possesses hair with characteristic length, color, shape, root appearance, and internal microscopic features that distinguish one animal from another. Considerable variability also exists in the types of hairs that are found on the body of an animal. In humans, hairs found on the head, pubic region, arms, legs, and other body areas have characteristics that can determine their origin. On animals, hair types include coarse outer hairs or guard hairs, the finer fur hairs, tactile hairs such as whiskers, and other hairs that originate from the tail and mane of an animal.

Because hairs can be transferred during physical contact, their presence can associate a suspect to a victim or a suspect/victim to a crime scene. The types of hair recovered and the condition and number of hairs found all impact on their value as evidence in a criminal investigation. Comparison of the microscopic characteristics of questioned hairs to known hair samples helps determine whether a transfer may have occurred.

Hair Microscopy

The examination of human hairs in the forensic laboratory is typically conducted through the use of light microscopy. This examination routinely involves a two-step process-the identification of questioned hairs and the comparison of questioned and known hairs. The purpose for conducting this examination is to ascertain whether two or more individuals could have come into contact or whether one or more individuals could have come into contact with an object. This associative evidence is particularly useful in crimes of violence, such as homicide, sexual assault, and aggravated assault, where physical contact may have occurred. Crimes such as burglary and armed robbery typically involve the recovery of debris and articles of clothing which may contain hairs useful for the identification of suspects.

The value of hair evidence is related to the variability of hair characteristics between individuals in the population, which can be visualized through the use of comparison microscopy. There are many factors that impact on the reliability of a hair association, including experience, training, suitability of known hair standards, and adequacy of equipment. Although hair evidence is a valuable tool in human identification, it is difficult to establish a statistical probability for a particular association due in part to the lack of reliable quantitative assessments of the microscopic characteristics present in hairs.

The comparison microscope consists of two compound light microscopes connected by an optical bridge that allows for the simultaneous viewing of questioned hairs and known hairs. Typically, a glass microscope slide containing known or reference hairs is positioned on the stage of one microscope, and a glass microscope slide containing a questioned hair or hairs is positioned on the stage of the other microscope. This enables the hair examiner to compare the microscopic characteristics of the known and questioned hairs in one field. The range of magnification used is approximately 40X to 400X.

The hair examination process involves many different steps, the first of which is to determine whether the hair in question originated from an animal or a human being. If the hair originated from an animal, it is possible to further identify it to a particular type of animal. Although certain hairs can be attributed to species, it is not possible to identify hairs to a specific animal to the exclusion of other similar animals. An example of this occurs when dog hairs can be associated to a particular breed but cannot be identified to a specific dog within that breed.

Hair Anatomy and Growth

Hair is present on many different regions of the body. Each region, such as the head, pubic area, chest, axillae, and limbs, has hairs with microscopical characteristics attributable to that region. Although it is possible to identify a hair as originating from a particular body area, the regions of the body that are primarily used in forensic comparisons are the head and pubic areas. As hairs undergo a cyclical growth (anagen) and resting phase (telogen), the visible microscopic characteristics are sufficient to determine the phase of growth of the hair.

During the anagen phase, the hair is actively growing, and materials are deposited in the hair shaft by cells found in the follicle. Metabolically active and dividing cells above and around the dermal papilla of the follicle grow upward during this phase, to form the major components of the hair-the medulla, cortex, cuticle, and accompanying root sheath. In the telogen phase, the follicle is dormant or resting. The transition period between the anagen and telogen phases is referred to as the catagen phase.

Hairs are routinely lost during the telogen phase and often become a primary source of evidentiary material. An example of this natural shedding process can be seen when one combs through the hairs on the head. It is not uncommon for hairs of this type to be transferred to another individual or to an object during physical contact. Hairs can also become dislodged from the body while they are in an actively growing state, such as by pulling or by striking with an object. The microscopical appearance of the root area will allow for the determination of the growth phase.

On a healthy head, 80 to 90 percent of the hair follicles are in the anagen phase, 2 percent are in the catagen phase, and 10 to 18 percent are in the telogen phase. Once the hair reaches the telogen phase, the follicles have achieved a mature, stable stage of quiescence. During the telogen phase, the hair is anchored in the follicle only by the root, which is club-shaped. The germ cells below the club-shaped root will give rise to the next generation of an anagen hair. The replacement of human scalp hair occurs in a scattered mosaic fashion with no apparent wave-like or seasonal pattern. The average period of growth for scalp hair is approximately 1,000 days; the resting phase lasts about 100 days. Approximately 10 percent of the hairs on a human head (100/1000), therefore, are in the quiescent telogen phase, and a minimal amount of force-such as that from combing-is required to dislodge the hairs from the dormant follicle.

The basic morphology of human hairs is shared by each individual in the population, but the arrangement, distribution, and appearance of individual microscopic characteristics within different regions of hair routinely allow a skilled hair examiner to differentiate hairs between individuals. An analogy would be the ability of an individual to recognize the face of a friend or relative in a crowd even though each person in the crowd possesses ears, eyes, a nose, and a mouth.

Animal Hairs

Animal hairs discovered on items of physical evidence can link a suspect or location to a crime of violence. A victim placed in a vehicle or held at a location where animals are routinely found often results in the transfer of animal hairs to the victim's clothing. Cat or dog hairs can be found on the adhesive portions of ransom and extortion notes prepared by pet owners. The transfer of pet hairs to the victim or crime scene may also occur when the suspect is a pet owner and has animal hairs on his or her clothing when the contact occurs. This is referred to as a secondary transfer of trace material.

When an animal hair is found, it is identified to a particular type of animal and microscopically compared with a known hair sample from either an animal hair reference collection or a specific animal. If the questioned hair exhibits the same microscopic characteristics as the known hairs, it is concluded that the hair is consistent with originating from that animal. It is noted, however, that animal hairs do not possess enough individual microscopic characteristics to be associated with a particular animal to the exclusion of other similar animals.

Animal hairs found at crime scenes or on the clothing of suspects and victims may also have originated from a fur coat or pelt. These hairs may have been artificially colored or trimmed and often do not have a root. It is preferred that the entire fur garment be obtained so that suitable known samples can be submitted for comparison.

Human Hairs

As stated previously, physical contact may result in the transfer of hairs. These can transfer directly from the region of the body where they are growing-a primary transfer-or they can transfer from the clothing of individuals-a secondary transfer. It has been reported that approximately 100 head hairs are shed by an individual each day. These hairs are shed on clothing and on items in the environment. Contact between a victim and a suspect's environment can easily cause a secondary transfer of hair. Hairs that are found on the clothing of suspects or victims and appear to have fallen out naturally may be the result of primary or secondary transfer. Hairs that have been forcibly removed may suggest a violent confrontation.

Body Area Determination

The body area from which a hair originated can be determined by general morphology. Length, shape, size, color, stiffness, curliness, and microscopic appearance all contribute to the determination of body area. Pigmentation and medullar appearance also influence body area identification. Hairs that exhibit microscopic characteristics shared by different anatomical areas are often referred to as body hairs. These include hairs found on the upper legs, lower abdomen, and back. Because there is a wide range of interpersonal variation in head and pubic hairs, the majority of work in forensics has been in comparing and differentiating hairs from the head and pubic regions.

Head Hairs
Head hairs are usually the longest hairs on the human body. They are characterized as having a uniform diameter and, often, a cut tip. Head hairs can appear uncut, with tapered tips but are more often cut with scissors, razors, or clippers. In general these hairs are subject to more alteration than hairs from other body areas. Alterations to the natural appearance of hair include use of hair dyes, rinses, permanents, frosts, and other chemical applications. Environmental alterations can result from exposure to excessive sunlight, wind, dryness, and other conditions. Because these hairs can be affected by a number of environmental and chemical conditions, it is recommended that head hair samples be obtained as soon as possible from suspects and victims of crime. Head hair samples obtained years after a crime are generally not suitable for meaningful comparison purposes.

As head hairs are routinely compared in a forensic laboratory, it is important to obtain suitable known samples from suspects and victims and possibly from other individuals (elimination samples). The known sample should contain a random sampling of hair from different areas of the scalp. The number of hairs required for a meaningful comparison may vary depending on the uniformity of characteristics present in the hairs from an individual. Because this is not known when the hair sample is taken, obtain at least 25 full-length hairs. This hair sample should include both plucked and combed hairs, packaged separately.

Pubic Hairs
Pubic hairs are also routinely compared in a forensic laboratory. As with head hairs, considerable variation exists between individuals in the population. Pubic hairs are not subject to as much change as head hairs over time, and because of this, a sample taken a year or more after a crime may still be suitable for meaningful comparison purposes. It is recommended that a known pubic hair sample be obtained as soon as possible after a crime and should contain at least 25 full-length hairs taken from different areas of the pubic region.

Pubic hairs are generally coarse and wiry in appearance. They exhibit considerable diameter variation or buckling and often have a continuous to discontinuous medulla. While tapered tips are common, these hairs may also be abraded or cut.

Facial Hairs
Facial hairs are more commonly called beard hairs or mustache hairs. These hairs are coarse in appearance and can have a triangular cross section. Heavy shouldering or troughs in the hair are observed under magnification. Other characteristics include a wide medulla and a razor-cut tip.

The presence of facial hairs on the clothing of a suspect or victim may help establish contact between these individuals. While these hairs may be compared microscopically, the significance of the association may not be as great as head hair and pubic hair associations.

Limb Hairs
Hairs from the legs and arms constitute limb hairs. These hairs are shorter in length, arc-like in shape, and often abraded or tapered at the tips. The pigment in limb hair is generally granular in appearance, and the medulla is trace to discontinuous.

While limb hairs are not routinely compared in a forensic laboratory, they can differ in appearance between individuals. These differences, however, are not considered sufficient to allow limb hairs to be of value for meaningful comparison purposes. The presence of leg or arm hairs on certain items of evidence may help to corroborate other investigative information.

Fringe Hairs
Hairs originating from areas of the body outside those specifically designated as head or pubic are generally not suitable for significant comparison purposes. These hairs might originate from the neck, sideburns, abdomen, upper leg, and back.

Other Body Area Hairs
Axillary (underarm) hairs, chest hairs, eye hairs, and nose hairs are not routinely compared. As with limb hairs and fringe hairs, their presence may help to corroborate information obtained during an investigation.

A human hair can be associated with a particular racial group based on established models for each group. Forensic examiners differentiate between hairs of Caucasoid (European ancestry), Mongoloid (Asian ancestry), and Negroid (African ancestry) origin, all of which exhibit microscopic characteristics that distinguish one racial group from another. Head hairs are generally considered best for determining race, although hairs from other body areas can be useful. Racial determination from the microscopic examination of head hairs from infants, however, can be difficult, and hairs from individuals of mixed racial ancestry may possess microscopic characteristics attributed to more than one racial group.

The identification of race is most useful as an investigative tool, but it can also be an associative tool when an individual's hairs exhibit unusual racial characteristics.

Caucasoid (European)
Hairs of Caucasoid or Caucasian origin can be of fine to medium coarseness, are generally straight or wavy in appearance, and exhibit colors ranging from blonde to brown to black. The hair shafts of Caucasian hairs vary from round to oval in cross section and have fine to medium-sized, evenly distributed pigment granules.

Mongoloid (Asian)
Hairs of Mongoloid or Asian origin are regularly coarse, straight, and circular in cross section, with a wider diameter than the hairs of the other racial groups. The outer layer of the hair, the cuticle, is usually significantly thicker than the cuticle of Negroid and Caucasian hairs, and the medulla, or central canal, is continuous and wide. The hair shaft, or cortex, of Mongoloid hair contains pigment granules that are generally larger in size than the pigment granules of Caucasian hairs and which often appear to be grouped in patchy areas within the shaft. Mongoloid hair can have a characteristic reddish appearance as a product of its pigment.

Negroid (African)
Hairs of Negroid or African origin are regularly curly or kinky, have a flattened cross section, and can appear curly, wavy, or coiled. Negroid pigment granules are larger than those found in Mongoloid and Caucasian hair and are grouped in clumps of different sizes and shapes. The density of the pigment in the hair shaft may be so great as to make the hair opaque. A Negroid hair shaft exhibits variation or apparent variation in diameter because of its flattened nature and the manner in which it lies on the microscope slide. Twisting of the hair shaft, known as buckling, can be present, and the hair shaft frequently splits along the length.

Age and Sex

The age of an individual cannot be determined definitively by a microscopic examination; however, the microscopic appearance of certain human hairs, such as those of infants and elderly individuals, may provide a general indication of age. The hairs of infants, for example, are generally finer and less distinctive in microscopic appearance. As individuals age, hair can undergo pigment loss and changes in the configuration of the hair shaft to become much finer and more variable in diameter.

Although the sex of an individual is difficult to determine from microscopic examination, longer, treated hairs are more frequently encountered in female individuals. Sex can be determined from a forcibly removed hair (with tissue), but this is not routinely done. Definitive determination of sex can be accomplished through the staining of sex chromatin in the cells found in the follicular tissue, but nuclear DNA and mitochondrial DNA (mtDNA) tests will provide more specific information regarding the possible origin of the hair.

The presence of artificial treatment such as dyes or rinses can be identified through microscopical examination. Inasmuch as head hairs grow at the rate of one centimeter per month, the approximate time of this treatment can be determined by measuring the length of untreated area of the hair. A direct, side-by-side comparison of the color of the questioned and known artificially treated hairs is typically conducted by a hair examiner.

As stated previously, the condition of the root area of a hair allows the hair examiner to microscopically determine whether the hair was forcibly removed from the body or shed naturally. Hairs that fall out naturally have a club-shaped root, whereas a forcibly removed hair will be stretched and may have tissue attached to it. The manner in which a hair was removed can have considerable value, especially when there is a possibility of violent contact between a suspect and a victim. The identification of burned, cut, or crushed hairs can also be established through microscopic examination.

Biological or Environmental Alteration

The microscopic appearance of hairs is affected by natural biological fluctuations and environmental influences. For this reason, it is important that known hair standards are collected contemporaneously to the deposition of questioned hairs. Head hairs are most affected by these factors, whereas pubic hairs are less influenced. A time period of several months to years can detract from a meaningful head hair comparison, whereas several years may not severely impact on meaningful pubic hair comparisons.

When hairs originate from a body in a state of decomposition, a dark band may appear near the root of the hair. This characteristic has been labeled a postmortem root band.

Conclusions

There are several possible conclusions that can be reached from the microscopic examination and comparison of human hairs. When the questioned hair(s) is compared to the known hairs using a comparison microscope, the full length of the hair(s) as well as the full range of microscopic characteristics must be considered. Following their analyses, hair examiners may conclude the following:

The questioned hair exhibits the same microscopic characteristics as the hairs in the known hair sample and, accordingly, is consistent with originating from the source of the known hairs.

The questioned hair is microscopically dissimilar to the hairs found in the known hair sample and, accordingly, cannot be associated to the source of the known hairs.

Similarities and slight differences were observed between the questioned hair and hairs in the known hair sample. Accordingly, no conclusion could be reached as to whether the questioned hair originated from the same source as the known hairs.

When a hair exhibits the same microscopic characteristics as hairs in the known hair sample, a qualifying statement may be added to the report. This statement may read as follows:

Hair comparisons are not a basis for absolute personal identification. It should be noted, however, that because it is unusual to find hairs from two different individuals that exhibit the same microscopic characteristics, a microscopic association or match is the basis for a strong association.

Significance of Hair Evidence

The significance of hair examination results is dependent on the method of evidence collection used at the crime scene, the evidence processing techniques employed, the methodology of the hair examination process, and the experience of the hair examiner. Head hairs and pubic hairs are routinely held as more significant than hairs from other body areas.

Certain case situations affect the significance of identifying hairs. When a family member may be involved in a crime, the location, number, and condition (forcibly pulled or burnt, for example) of recovered hairs may be important. The involvement of the victim's associates, including dates, coworkers, and other people who may have logical contact with or access to the victim and/or crime scene is an additional consideration in hair examinations. Situations involving strangers have greatest significance when hair associations have been made.

Questions concerning hair examinations and their significance include:

Is the significance of a hair association dependent on a set number of compared characteristics?

Does the length of the compared hairs affect the significance of an association?

Does treatment influence the significance?

Are hairs of specific racial groups more significant than others?

Do hair sprays, gels, or other hair applications influence the significance of a hair match?

Is a hair match significant when the comparison was made with a limited number of known hairs?

The hair identification process involves the examination and comparison of hair characteristics along the entire length of the hair(s). Longer hairs have more characteristics to compare, and the greater the variation along the length, the greater the degree of significance.

The value of the evidence in establishing a particular association can be influenced by

the probability that the association (or elimination)
was due to coincidence,

the probability that the association (or elimination)
was due to examiner error, and

the probability that there is an alternative
explanation for the evidence, such as secondary transfer,
contamination, or deliberate planting.

The significance of a hair match is influenced by how often the examiner has seen certain characteristics as well as by how often the examiner has seen hairs of a particular race or body area.

The range of opinions concerning hair examinations includes:

Nothing about hair is comparable to the specificity of fingerprints, and at best, the probability of establishing identification from hair is no greater than the probability of determining identification using the ABO blood group system;

Research studies have shown that hairs from two individuals are distinguishable; that no accidental or coincidental matches occurred; and that such accidental or coincidental matches would, in actual casework, be a relatively rare event; and

The significance of a hair match is a median point between the above statements.

It has also been stated that hair evidence is only of value when used in conjunction with other evidence.

Positive hair comparison conclusions may be weakened by the presence of incomplete hairs; by common, featureless hairs; and by known samples with large intrasample variation. Conversely, positive hair comparison conclusions are strengthened by the presence of two or more mutually dissimilar hairs that are similar to a known sample; by hairs with unusual characteristics; by two-way transfers; and by additional examinations of confirmation, such as DNA and sex-typing.

Normal negative hair comparison conclusions are weakened by deficiencies in the known hair sample, including too few hairs, unrepresentative hairs, incomplete hairs, and a significant temporal difference between the offense and the collection of the known sample. Negative hair comparison conclusions are also weakened by the presence of incomplete questioned hairs and by similarities and differences within the hair sample.

Factors which strengthen normal negative hair comparison conclusions include a large quantity of known sample hairs; little intrasample variation within the known sample; and hairs that are very dissimilar, such as those exhibiting distinct racial and/or microscopic characteristics. Two or more questioned hairs that are found together in a clump and are dissimilar to the known sample will also support a negative hair comparison conclusion.
To Fiber Evidence To Crime and Evidence

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Hairs, Fibers, Crime, and Evidence, Part 1, by Deedrick (Forensic Science Communications, July 2000)

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Hairs, Fibers, Crime, and Evidence, Part 1, by Deedrick (Forensic Science Communications, July 2000) July 2000 - Volume 2 - Number 3 Part 1: Hair Evidence Unit Chief Trace Evidence Unit Federal Bureau of Investigation Washington, DC Hair Evidence | Hair Microscopy | Hair Anatomy and Growth | Animal Hairs

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hair being tested and shows how DNA is proved.

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Hairs, Fibers, Crime, and Evidence, Part 3, by Deedrick (Forensic Science Communications, July 2000)

July 2000 - Volume 2 - Number 3

Hairs, Fibers, Crime, and Evidence Part 3: Crime and Evidence

Unit Chief
Trace Evidence Unit
Federal Bureau of Investigation
Washington, DC

Introduction | Crime Scene Search | Evidence Collection | Evidence Handling Procedures
Protocol for Evidence Processing in the FBI Laboratory
Examination Conclusions

The manner in which a crime scene is searched is determined by the type of crime, the location of the scene, details concerning events of the crime, the time of day, the number of people available for the search, and available equipment. Inasmuch as hair and fiber evidence can play a role in most cases involving violent crime, serious consideration should be given to collecting it properly. Once the crime has been committed, little time remains before hair and fiber evidence will be lost or contaminated. The importance of securing the crime scene cannot be overstated.

Crime Scene Search

When physical contact occurs between two individuals, objects, or individuals and objects, there is a likelihood of transfer of hair and fiber evidence. This likelihood is dependent on the nature of the contact, the duration of the contact, and the nature of the contacting surfaces. The direct transfer of hairs from the head of an individual to the clothing of another individual is called a primary transfer. When hairs have already been shed and are transferred to an individual, it is called secondary transfer. Fibers are transferred in a similar manner. When fibers are transferred from the fabric of an individual's clothing to the clothing of another individual, it is called a primary transfer. As these same fibers are transferred to other objects during subsequent contacts, secondary transfers are occurring.

It is important for crime scene investigators to understand the mechanisms of primary and secondary transfer. As trace evidence can be transferred during the commission of a crime, it can also be transferred during the search process. Hairs and fibers can not only be picked up inadvertently by investigators, they can be inadvertently deposited at the crime scene. The following are considerations at the crime scene:

Elimination hair and/or fiber samples may need to be obtained from personnel conducting the search.

Prioritize the order of evidence collection. Collect large items first and then proceed to the trace evidence. USE CAUTION WHEN WALKING THE CRIME SCENE.

Once the trace evidence is collected via vacuuming, taping, or tweezing, take blood samples, remove bullets, dust for fingerprints, and so on.

Processing the crime scene for fingerprints prior to trace evidence collection is not recommended because it can

Inadvertently transfer trace evidence onto the clothing of the technicians,

Move trace evidence, and/or

Contaminate trace evidence with dusting powder.

Evidence Collection

The following are suggestions for collecting evidence from crime scenes such as houses, apartments, and vehicles:

Photograph all evidence prior to removing it.

Remove larger items or debris from carpeting or walk areas prior to other examinations. Consider wearing disposable booties.

Collect large items, such as clothing, and place them in separate paper bags. Keep an accurate evidence log. One person should collect and bag the items while another person labels the bags and records the items in the log.

Do not place all clothing items from a suspect in one paper bag, nor all items from a victim in another bag. Bag each item separately.

Never put suspect items and victim items in contact with one another. The person collecting the suspect's items should not be the same person that collects the victim's items. If this must occur, personnel must change their clothing and collect the evidence at a different time to avoid contamination.

Bedding should be carefully handled to avoid loss of hairs and fibers. Each item should be placed in a separate bag.

Floor surfaces should be vacuumed for possible trace evidence. Some crime scene investigators use tape to secure trace evidence; however, tape is generally difficult to work with at the scene and in the laboratory. Smaller surfaces such as chairs and car seats can be taped or vacuumed.

Ensure that carpet, pet hair, and other standards that might have transferred to a suspect or victim are collected.

Always process for fingerprints after collecting trace evidence.

Collect all possible known fiber samples from a vehicle. These may be obtained from the carpet, door panels, headliner, seats, floor mats, and trunk.

The following suggestions pertain to different types of items recovered at the crime scene:

Hairs found in the hands of the victim usually belong to the victim. Rarely are the hairs similar to the suspect's known hairs; nevertheless, these must be collected and submitted for analysis.

Pubic and head hair combings should always be taken in violent crimes. Foreign hairs as well as fibers can be recovered from these samples. If a hat is recovered at the crime scene and a suspect is identified soon, it may be possible to find fibers similar to those in the hat in the suspect's hair.

Thorough random samples should be taken from the head and pubic regions of a suspect(s) and
victim(s). Twenty-five full-length hairs, pulled and combed from different areas of the head and pubic regions, are generally considered an adequate representation of an individual's hair characteristics.

Doors and windows should be searched for trace evidence if they are possible points of entry or exit.

Evidence Handling Procedures

Once the evidence has been collected, there are several recommendations or considerations when packaging it for transmittal to the laboratory. Clothing items must be packaged in separate sealed paper bags-not plastic. To avoid contamination, clothing items from the suspect should never be handled in the same area in which items from the victim are handled. All damp or blood-soaked items must be air-dried in a room away from air movement and traffic. Drying paper placed under damp clothing items should be submitted separately.

Submit individual hairs and fibers in clean paper or in an envelope with sealed corners. The primary paper or envelope should be placed inside a secondary sealed envelope with all corners taped. Many times individual hairs identified on items of clothing are not removed or secured. These hairs may move or be lost, so it is recommended that they be removed and placed in an envelope (first noting where they were removed).

If a floor surface is vacuumed, the debris should be placed on a white sheet of paper (8 x 11 inches) and folded at the corners. This paper should be placed in a heat-sealed or resealable plastic bag.

Protocol for Evidence Processing
in the FBI Laboratory

When evidence is received in the Trace Evidence Unit, the case is assigned to an examiner. The examiner will read the incoming communication to determine the nature of the offense, the names of the suspects and victims, and the types of requested examinations. It is important to have an understanding of the offense to help determine the course of action in the Laboratory. Contact between family members or friends would be treated differently, as the transfer of trace evidence would be more likely in these cases.

In the Unit, there are three processing rooms designed for debris collection. Debris is collected through a combination of picking, scraping, and sometimes taping. Whereas taping is considered by some laboratories to be a preferred technique, it can be time-consuming and tedious and can present a storage problem for the tape collections. Vacuuming is not recommended for clothing items. The clothing of a victim is processed in a room other than the room in which the suspect's clothing is processed. The collected debris is placed in pillboxes and examined with a stereobinocular microscope. Hairs and fibers are mounted on glass microscope slides for identification and comparison purposes.

Collecting trace evidence using scraping and picking techniques

Collecting trace evidence
with a vacuum

Examination Conclusions

When a questioned hair exhibits the same microscopic characteristics as the known hairs of an individual, the hair could have originated from that individual. If the questioned hair is microscopically dissimilar to the known hair standard, it cannot be associated with the individual. Different people generally have different hair characteristics, but differences in microscopic characteristics can also be the result of time and alteration. Known hair samples should be collected from individuals as soon as possible to the date of the crime. As time passes, microscopic characteristics can change, and the individual may alter the color with dyes.

Stereomicroscopic examination

If a fiber exhibits the same microscopic and optical properties as a known fabric, the fiber could have originated from that fabric. Although it is not possible to say that a fiber originated from a particular fabric, fiber matches are not insignificant. Because of the many different types of fibers and fabrics and the many different ways they can be colored, the likelihood of finding coincidental matches is low. It is possible, however, to positively say that a torn piece of fabric originated from another fabric if the torn edges match.

For more information about trace evidence and the recovery of evidence from crime scenes, see the Hairs and Fibers and Crime Scene Search sections of the Handbook of Forensic Services.
To Hair Evidence To Fiber Evidence

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Hairs, Fibers, Crime, and Evidence, Part 3, by Deedrick (Forensic Science Communications, July 2000)

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Hairs, Fibers, Crime, and Evidence, Part 3, by Deedrick (Forensic Science Communications, July 2000) July 2000 - Volume 2 - Number 3 Hairs, Fibers, Crime, and Evidence Part 3: Crime and Evidence Unit Chief Trace Evidence Unit Federal Bureau of Investigation Washington, DC Introduction | Crime Scene Search | Evidence

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Humans shed an average of approximately 100 head hairs per day, and because hair can be easily transferred during physical contact it is commonly submitted as forensic evidence to help establish associations between people (e.g. a victim and suspect) and/or people and a crime scene.

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Hair is being Examined - Jalen Harpe

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How Hair is packaged- Jalen Harpe

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A cluster of hairs found in the clutches of a victim's hand could be placed into a small stoppered plastic bottle (called a polypot) and this then placed into a clear polythene evidence bag.
https://castleviewuk.com/ch1-packaging.html

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https://projects.nfstc.org/property_crimes/module03/pro_m03_t08.htm

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https://archives.fbi.gov/archives/about-us/lab/forensic-science-communications/fsc/april2009/review/2009_04_review02.htm

Gavyn Fountain

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April 2009 - Volume 11 - Number 2

Introduction | Scientific Basis for Microscopic Hair Examinations | Microscopic Characteristics-Hair Identification Transfer and Persistence of Hairs | Hair-Collection Process | Race and Body-Area Identification | Procedure for Microscopic Hair Comparisons | Studies Supporting Microscopic Hair Comparison | DNA Analysis of Hairs | Conclusions | Acknowledgment | References

Hair evidence is one of the most common types of evidence encountered in criminal investigations. During the course of the normal hair-growth cycle, hairs are readily lost from individuals, and these hairs may be transferred during the course of a criminal activity.

Edmond Locard was the first forensic scientist to formally articulate the foundation for the transfer event (Locard 1930). Now known colloquially as the Locard Exchange Principle, it states that any time there is contact between two surfaces, an exchange of materials will occur. One of the materials that can be readily collected, identified, and compared is hair evidence.

The forensic analysis of hair evidence can be extremely valuable in the examination of physical evidence by (1) demonstrating that there may have been an association between a suspect and a crime scene or a suspect and a victim or (2) demonstrating that no evidence exists for an association between a suspect and a crime scene or a suspect and a victim. Although the science of microscopic hair examination can never result in an identification, that is, conclude that a hair came from one individual to the exclusion of all others, the vast amount of both macroscopic and microscopic information available from hair analysis can provide a strong basis for an association and certainly provides strong exculpatory evidence. The final aim of any forensic examination must be to provide statements based on objective scientific observation that will be of value in a court of law or to any interested party involved in an investigation.

The purpose of this document is to review the bases for microscopic hair analysis and comparison. Hair examinations involve the analysis and comparison of the morphological characteristics present in hair. Based on these morphological characteristics, the first determination that can be made is whether the hair came from a human or an animal (for the purposes of this document, any reference made to animal means nonhuman animal). Within each of these two groups, additional information regarding the potential donor can be obtained using these same microscopic characteristics. Finally, a comparison can be conducted between a hair of unknown origin and a known sample of hairs from an appropriate known sample

All organisms differ widely in many dimensions, including morphological appearance, physiology, and genetic makeup. Some groups of organisms clearly are more similar to some groups than to others. For instance, a monarch butterfly is more similar to a tiger swallowtail butterfly than either is to a ladybird beetle. Biologists seek to identify these differences and use them to organize and classify the world around them. They use these differences to generate classification schemes that can be used for many purposes, from examining how traits evolve to solving crimes.

These classification schemes have their roots in the field of taxonomy. Taxonomy is the practice of classifying biodiversity, and it has a long and venerable history. In 1758, Carl Linnaeus proposed a system that has dominated classification for centuries. He proposed a system of binomial nomenclature to describe living organisms (as cited in Wikipedia 2009). However, the term taxonomy is now applied in a wider, more general sense and refers to a classification of things, as well as to the principles underlying such a classification. Almost anything-animate objects, inanimate objects, places, concepts-may be classified according to some scheme.

Evaluation of shared and distinguishing characteristics is essentially the process used in forensic hair examinations. The microscopic characteristics allow for hair to be categorized into smaller groups, such as human or animal, racial group, body area, color, phase of growth, etc. This is considered the identification phase, for example, classifying the hair as being human, exhibiting Caucasian characteristics, coming from the head, being brown in color, and possessing a telogen root.

The next phase of the examination process is conducting a microscopic comparison. This involves evaluating the microscopic characteristics present in the hair samples, evaluating the points for comparison, and determining whether or not a questioned hair can or cannot be excluded as originating from the source of a known sample.

Hair comparisons are a combination of a pattern-recognition process and a step-by-step analysis of a questioned hair and a known sample. An example of the pattern-recognition process is the manner in which we identify a friend in a crowd of people. It is an instant recognition, based on our experience with that person. It is not conducted in a logical, step-by-step process, evaluating first the height, hair color, skin color, eye color, and other characteristics. It is an almost instantaneous evaluation of all of these characteristics together. The identification of our friend does not carry any less weight based on the mechanism we used to identify him or her.

The same process is used for hairs, but in a more methodical manner. In a microscopic hair comparison, the examiner is determining whether or not similar patterns of microscopic characteristics exist at each point of comparison along the hair shaft. This pattern-recognition process then continues in a step-by-step fashion along the length of the hair.

To be considered an association, the microscopic characteristics of a questioned hair also must be exhibited in the known sample. Forensic hair examination involves the analysis of objective characteristics and a subjective interpretation of the relative weight of these characteristics. The subjective component of hair examination almost dictates that two different examiners will place slightly different weight on individual characteristics or may describe these characteristics using slightly different words.

However, if two examiners have been trained properly, possess adequate experience, and use proper procedures, they should reach the same conclusion. Accordingly, the amount of experience gained by examining a large number of hairs and conducting a large number of hair comparisons is critical.

The scientific method involves generating a hypothesis and testing it to determine if it is false. In order for the hypothesis to be valid, it must be able to be supported repeatedly via reproducible experiments. This process distinguishes science from other professional endeavors. By establishing a reliable, repeatable set of procedures and criteria by which the results are evaluated, an objective scientific methodology can be achieved. This, coupled with a properly trained, qualified examiner operating within a rigorous quality assurance/quality control program, provides credible and reliable results.

Hair identification is not employed solely by forensic scientists. Hair identification is an important tool used by wildlife biologists, archeologists, anthropologists, and textile conservators. Many researchers have investigated the morphological characteristics of hair, devised keys, and reviewed the science of animal-hair identification (Appleyard 1960; Day 1966; Mathiak 1938; Mayer 1952; Moore 1974; Oyer 1939; Stains 1958, 1962; Wildman 1954, 1961; Williams 1938). These works have aided in ecological studies, food-habit studies, and law enforcement investigations by providing descriptions, keys, and photographs of the microscopic characteristics of animal hairs.

Brown (1942) attempted to develop a technique for identifying hairs and wools from various types of materials recovered from archeological works. Hausman (1930) used hair examination in his laboratory to perform archeological work, examine stomach remains, identify fur, and conduct legal proceedings.

Animal-hair studies also have been conducted within the field of forensic science. Peabody et al. (1983) determined that the medullary fraction could be used to reliably distinguish between dogs and cats. Hicks (1977) and Deedrick and Koch (2004a) described the microscopic characteristics that can be used to discriminate between animal hairs that are most likely to be encountered in forensic casework.

It is important to note that although microscopic analysis and comparison of animal hairs can be conducted, the significance ascribed to an animal-hair association often is less than that of a human-hair association. Accordingly, when an animal-hair association is reported, this decreased significance must be highlighted. For example, in a report for a dog-hair association, the FBI Laboratory would use a statement similar to the following:

It should be noted that dog hairs do not possess enough individual microscopic characteristics to associate a questioned hair to a particular dog to the exclusion of other dogs of a similar breed.

Despite the difference in the significance of animal-hair comparisons to human-hair comparisons, it does not detract from its potential usefulness in a forensic investigation. The presence of a dog hair on an item from the victim that can be microscopically associated with the known hair sample from the suspect's dog may be very important.

Like the analysis of animal hair, the analysis of human hair is not conducted solely by forensic scientists. Hairs are analyzed by the cosmetics industry in the area of hair-care products and by the medical field in many areas such as nutritional status and toxic-element levels, as well as for certain dermatological diseases. However, the microscopic characterization and comparison of human hairs are largely the domain of forensic scientists.

The first reported use of forensic human-hair comparison was by Rudolf Virchow in 1861 (as cited in Bisbing 1982). He reported the following:

The greatest majority of the hairs of the victim represent a thorough and complete accord with the hairs found on the defendant that there exists no technical ground opposite to looking at the hairs found on the defendant as being the hairs of the victim. . . . However, the hairs found on the defendant do not possess any so pronounced peculiarities or individualities that no one with certainty has the right to assert that they must have originated from the head of the victim (as cited in Bisbing 1982).

Paul Kirk conducted some of the first studies on the potential forensic application of microscopic comparison of hair in the United States (Gamble and Kirk 1941; Greenwell et al. 1941; Kirk 1940). In addition to his publications on the microscopic characteristics of human hairs, he conducted hair-comparison studies using his criminology students. All of the students were required to compare a single hair to 20 known samples, where all of the known samples were of a similar color and from individuals of a similar age. He reported that no student who completed the routine examination failed to report the association correctly (Kirk 1940). He further stated that although this falls short of individualization, the following five factors must be considered:

(a) that twenty suspects in a single crime is rather an exceptional number; (b) that the eliminative value of a failure to identify the hair as that of any of the suspects is great; (c) that time imposes on students a restriction on the total number of hairs that can be examined, and it is impossible as yet to say whether they could equally well pick, e.g., from 100 standards; (d) that in any random group of suspects there would be greater normal variations than are present in the selected group of similar hairs used for this exercise; and (e) that the students in question have never before examined hairs and are in no sense experts in this examination (Kirk 1940).

Based on his work, Kirk expected that it would be likely to make a determination of individuality using human-hair comparison. Obviously, this has not yet occurred, nor will it likely ever occur. However, his work laid much of the foundation for the methods of microscopic human-hair comparison that remain in use today.

Many characteristics must be considered in microscopic hair identification (Bisbing 1982; Deedrick and Koch 2004b; Hicks 1977; Kirk 1974; Lee and DeForest 1984; Moore 1974; Robertson 1999; Saferstein 1995; Seta 1988). Three distinct anatomical regions are associated with hair: the cuticle, the cortex, and the medulla. Using a wooden pencil as an analogy, we can think of the cuticle as the paint on the outside of the pencil, the cortex as the wooden portion of the pencil, and the medulla as the graphite.

The cuticle is the outermost layer of the hair. It protects the hair from environmental insults. The cuticle is composed of flattened, scale-like cells, which overlap one another much like the scales on a fish or shingles on a roof. These scales slope outward from their attachment point on the cortex, and their free ends point toward the tip of the hair. The free ends interlock with the cells of the inner root sheath and hold the hair in the follicle. In human hairs, the scales form an imbricate pattern, that is, they have no repeating pattern. This characteristic serves to distinguish human hairs from animal hairs; many animal hairs have a very regular, repeating pattern to their scales.

A number of microscopic characteristics associated with the cuticle are used in a hair comparison. The thickness of the cuticle, the variation in the thickness, the presence of pigment, and the color are all useful characteristics. In addition, the nature of the outer cuticular margin may be smooth, looped, ragged, or damaged. When damage or artificial treatment to the hair is extreme, the cuticle may be removed, thereby causing damage to the next innermost region of the hair, the cortex.

The cortex is the main body of the hair and contains many of the characteristics used in the microscopic comparison process. The cortex is composed of elongated and spindle-shaped cells. The cortex contains the structures that primarily give hair its color, the pigment granules. There are two chemical forms of pigment in human hairs: eumelanin and phaeomelanin. The pigment eumelanin manifests in the colors of brown and black, and phaeomelanin in the colors of yellow and red, with each pigment having a slightly different size and shape. From a forensic standpoint, the organization, density, size, and distribution of these pigment granules are the most informative features of the cortex. They vary tremendously between racial groups, between individuals, and, to a much lesser extent, even within an individual.

In addition to pigment granules, small air spaces called cortical fusi are found in the cuticle. These air spaces form during the keratinization process of the hair. They are readily observed with compound microscopy and are typically found near the root end of the hair.

The final structures associated with the cortex are the ovoid bodies. These are large, well-defined, oval-shaped structures that may be found dispersed throughout the hair. According to Robertson (1999), ovoid bodies are well-defined, highly dense clumps of undispersed pigment. Their presence is not rare in human hair, but neither are they commonly seen.

In addition to the cortical structures just discussed, a number of characteristics are associated with the cortical cells themselves. Their texture, size, damage, and shape are all useful characteristics in the comparison process.

Another region of the hair is the innermost layer of cells called the medulla. This layer of cells may be continuous, discontinuous, fragmentary, or absent. In animal hairs, the medullary structure often is used to identify the family and sometimes the species of animal. In comparison to animal hairs, human hairs have no regular structure or pattern. The medullary cells may appear opaque or translucent or may vary even within a single hair. The opaque regions contain trapped air, and the translucent regions are caused by the mounting medium's having displaced the air. The diameter of the medulla is also a useful characteristic in the identification and comparison process.

In addition to the three anatomical regions of the hair, many other characteristics are useful in the microscopic comparison process. These characteristics relate to the growth stage, environmental influences, and disease influences on the hair.

The nature of the root may contribute information regarding the species of origin of the hair, and in addition, the growth stage of the hair when it was separated from the body. In animal hairs, the root morphology may assist in the identification of the group of animals from which the hair came. For example, the hairs of dogs, cattle, horses, and members of the deer family have very distinct root morphologies from one another and from humans. In human hairs, the nature of the root depends on the growth stage of the hair. Many authors have offered classification schemes for the description of hair roots (Bisbing 1982; Harding and Rogers 1984; Lee and DeForest 1984; McCrone 1982; Shaffer 1982; Strauss 1983).

Hair grows from the dermal papillae, which lie in the base of the hair follicle. As new material is added to the hair, the "older" portion of the hair is slowly pushed out of the follicle until the hair naturally sheds from the body. At any given time, between 80 and 95 percent of the hairs on the human body are in an actively growing, or anagen, phase (Orentreich 1969; Pinkus 1981; Zviak and Dawber 1986).

The presence of an anagen root implies that some amount of force was required to remove the hair from the body (Ludwig 1969). The hair is still actively growing and is therefore still attached to the follicle. No statement can typically be made as to how much force was required; however, one would not expect to see this stage of root on hairs that fell from the body as a normal part of daily activities.

The second growth phase of hair is a transitional stage, called the catagen stage. During this short phase, the bulbous root of the hair begins to develop. At any given time, approximately 2 percent of hairs are in this growth phase (Pinkus 1981). No consensus exists with regard to the microscopic characteristics that are specific to this growth phase.

The third and final growth phase of hair is the dormant stage, called the telogen stage. These hairs are characterized by decreased pigment near the root, lack of medullation near the root, and increased cortical fusi near the root (Petraco 1988). In telogen hairs, the bulbous root is fully formed and is no longer attached to the dermal papillae. The hair is anchored in the follicle because of the interlocking cuticular scales of the hair and the inner root sheath of the hair follicle. Approximately 10 to 20 percent of the hairs are in this growth phase (Orentreich 1969; Pinkus 1981; Zviak and Dawber 1986).

In addition to the characteristics resulting from the growth phase of the hair, other characteristics are associated with the root. At times, when hairs are forcibly removed, follicular material may be attached. This material may be suitable for nuclear DNA analysis, if warranted. In forensic cases, hairs from dead bodies are sometimes examined. The decomposition process can impart specific characteristics on hairs (Linch and Prahlow 2001; Petraco et al. 1988), which can be used in the comparison process.

Hair color depends on the pigment granules present in the hair and on the other physical properties that affect how light is transmitted through the hair. Hair color is a useful feature in the hair-comparison process. Within an individual, hair color will show a degree of variation. In fact, variation may be observed within a single hair because of differences in exposure to the environment. However, the degree of variation within an individual is less than the variation among individuals (Robertson 1999).

Many authors have offered classification schemes for hair color (Bisbing 1982; Gaudette and Keeping 1974; Harding and Rogers 1984; Lee and DeForest 1984; McCrone 1982; Robertson 1982; Strauss 1983; Trotter 1939). Regardless of the classification scheme used, the hue (color shade), the value (light versus dark), and the intensity (saturation) must be considered during the comparison process (Hicks 1977).

The tip, or the distal end, of the hair also can vary greatly in morphology. The tip of a newly formed hair will taper naturally to a point. As the hair is subjected to grooming, abrasion, cutting, and possibly artificial treatment, microscopic characteristics are imparted to the tip of the hair. As they have with hair roots and hair color, numerous authors have offered classification schemes for the nature of hair tips (Bisbing 1982; Gaudette 1976; Gaudette and Keeping 1974; Harding and Rogers 1984; Lee and DeForest 1984; Robertson and Aitken 1986; Shaffer 1982). Regardless of the classification scheme used, the nature of the tip must be considered during the comparison process.

The length of the hair should be considered, keeping in mind that hairs may have been cut in the time between the deposition of the hair at the crime scene and the collection of the known sample. Conversely, the known hair sample may have grown if a significant length of time has elapsed between the deposition of the hair and the collection of the known sample. These additional factors must be considered during the comparison process.

The diameter of the hair is another feature that can be used in the comparison process. The overall shaft diameter may range from very fine (40-50 micrometers) to very coarse (110-120 micrometers). The diameter of the hair plays a significant role in the classification of racial group and determination of the body area from which the hair may have arisen.

The presence of artificial treatment may give the hair a characteristic color. Bleaching will remove pigment from the hair and give a Caucasian hair a characteristic yellow color. Dyes will add color to the hair and often result in a hair color that is outside the normal range of color expected in human hairs. Repeated artificial treatments will result in distinct regions of varying color.

When an artificial treatment is applied to the hair, it often results in a line of demarcation, that is, a notable change in color along the length of the hair. This is due to the treatment's interaction with the hair shaft down to the skin layer. As the hair continues to grow, the newly formed hair is not subjected to the same treatment and retains its natural color, resulting in the line of demarcation between the treated and untreated areas. Artificial treatment may also result in changes to the color of the cuticle, either within the cells of the cuticle or on the exterior of the cuticle.

Any damage present in the hair also should be noted. Cutting a hair with scissors typically results in a sheared or squared-cut appearance. This can be contrasted with hairs that are cut with a razor, which typically have an angular-cut appearance. Hairs that have been crushed, broken, burned, or chewed by insects all have very distinctive characteristics. These characteristics provide value to the comparison process, such as finding crushed or damaged hairs on a tool used to strike the head of the victim.

Diseases and other hair abnormalities may be informative to the hair-comparison process. A number of diseases may cause specific microscopic characteristics to appear in the hair. Seta et al. (1988) summarized the diseases and abnormalities that can result in these characteristics. Because these disease conditions are very rare, considerable weight is given to the presence of these characteristics.

Hairs are remarkably robust, retaining their comparable microscopic characteristics for a very long time, making them very suitable for forensic analysis. Hairs recovered from Ice Age sites, between 10,000 and 18,000 years old, were still able to be identified as human hairs. In fact, one hair still had its follicle attached (Bonnichsen and Schneider 1995). In its reference collection, the FBI Laboratory has hair samples collected from mummies identified to be more than 2000 years old (Oien unpublished data).

The primary mechanism for the transfer of trace evidence is described by the Locard Exchange Principle (Locard 1930). Although there will always be a transfer of trace evidence, in some instances, the material exchanged may be too small to detect or may be rapidly lost. Numerous authors have addressed the transfer and persistence of fibers in forensic cases, including Kidd and Robertson 1982; Pounds and Smalldon 1975a, 1975b, 1975c; and Robertson et al. 1982.

These authors investigated the mechanisms involved in the transfer of textile fibers and the persistence of the fibers after the transfer occurred. Although these studies primarily involved textile fibers, wool fibers were used in these studies; therefore, the results of these studies also apply to human hair. These authors found that the number of fibers transferred depended on the amount of pressure involved in the contact and the duration of the contact.

With regard to persistence, these authors found that the nature of the recipient garment, the size of the transferred fiber, and the movement of the recipient garment had a dramatic effect. If the garment containing transferred fibers was worn, most fibers were lost rather quickly (within a few hours). If the garment containing transferred fibers was held in a fume hood, the rate at which fibers were lost was much lower.

Gaudette and Tessarolo (1987) stated that many of the variables affecting fiber transfer and persistence were also important in hair transfer and persistence. In order to document some of these variables, they conducted several experiments on hair transfer. They identified two mechanisms of hair transfer: primary and secondary transfer.

Primary transfer can be either direct (from person A's scalp to another location) or indirect (from person A's scalp to person A's environment and then to another location). Secondary transfer is an indirect transfer (from person A's environment to person B's environment to person C's environment). The authors demonstrated that secondary transfer of human scalp hair can and does occur in casework situations and that persistence of the transferred hair is similar to that previously found for fibers by Pounds and Smalldon (1975a, 1975b, 1975c). Robertson and Somerset (1987) conducted a similar study on persistence and found comparable results; that is, most transferred hairs are lost with normal wear after about three hours.

Quill (1985) recovered 81 hairs from his clothing over a 31-day period. Of the hairs that were suitable for microscopic comparison, all had been transferred from family members. Quill concluded that for a foreign hair to be present on clothing, close personal contact is required. Simons (1986) found that although most hairs are removed from clothing during the laundering process, some hairs do remain on clothing and hair transfers can occur as a result of the laundering process.

Peabody et al. (1985) investigated the shedding of hairs into various types of headgear. They found that the number of hairs shed varies with the type of headgear worn and with the individual. They also noted the importance of collecting head-hair combings, because the nature of the hairs shed in their study were more similar to the naturally shed hairs encountered in combings than to the hairs encountered in plucked, known head-hair samples.

Based on these studies, it can be concluded that it is reasonable to find hair evidence in forensic cases. Hair is ubiquitous in the environment and, therefore, may be transferred during a crime. However, it is imperative for proper and timely collection of evidentiary materials, including known hair samples, to occur if hair examinations are going to be valid, reliable, and meaningful.

In order for hair evidence to be meaningful, the hair must not only be transferred, it must persist and be recovered as evidence. There are two distinct locations where evidence recovery typically occurs: at the crime scene and at the laboratory. Because of the potential loss of hair evidence, it is crucial that evidentiary items be collected as soon as possible; properly packaged to prevent loss, contamination, or deleterious change; and transported to the laboratory expeditiously. Any additional handling or wear increases the likelihood that the evidence will be lost.

Once the evidentiary item is transported to the laboratory, it must be handled in much the same manner. If the evidentiary item is going to be subjected to a variety of forensic disciplines, it is imperative that the trace evidence (including the hairs) be recovered before these other disciplines analyze the evidence, to protect against loss, contamination, or deleterious change. A number of techniques may be employed to collect and preserve the debris from the evidentiary item, including but not limited to taping, scraping, picking, and vacuuming.

Once the debris has been collected and preserved, the next step involves low-magnification microscopic analysis of the debris. Using a stereomicroscope, the debris is examined, and hairs are removed from the debris and mounted on glass microscope slides. This allows the hairs to be examined using a high-magnification compound microscope. Depending upon the number of hairs encountered in the debris sample, all of the hairs can be mounted on glass microscope slides, or a representative sample can be mounted.

Two methods may be used in determining which hairs are mounted when a representative sample is employed. In the first method, a sample of each of the distinct types of hairs observed with the stereomicroscope can be mounted, that is, some of each color, length, diameter, and texture.

The second method involves using a targeted search. This may be used in cases where known hair samples are submitted along with the evidentiary items. The known samples may be examined and mounted first. Once proper precautions have been taken to prevent contamination (cleaning the work area, cleaning the tools, changing gloves), the debris from the evidentiary items is then examined. Hairs macroscopically similar to those in the previously mounted known hair samples can be identified and preserved on glass microscope slides.

After the hairs have been preserved on glass microscope slides, they can then be examined with a high-magnification compound microscope. Using magnification ranges from 50x to 400x, the microscopic characteristics can be observed. Based on the analysis of these microscopic characteristics, a number of possible determinations can be made.

A human hair can be classified into one of three racial groups: Caucasian, Negroid, or Mongoloid. A classification of Caucasian typically means of European descent. Negroid typically means of Sub-Saharan African descent. Mongoloid typically means of Asian or Native American descent. It must be understood that designation of these racial groups is based upon an evaluation of the microscopic characteristics present in the hair. The microscopic designation of racial group may or may not coincide with how a person self-identifies his or her racial group.

If a hair or a hair sample cannot be easily associated with a particular racial designation, these hairs may be described as either exhibiting mixed racial characteristics or as not classifiable to one of the three groups. Even if a hair or a hair sample cannot be classified as to race, it still may be of value for meaningful microscopic comparison purposes. The inability to classify a hair into only one of these three groups serves as an additional characteristic that can be used in the comparison process.

A human hair also can be classified as to the region of the body from which it came. Using the same features listed previously, this designation can be made with considerable accuracy. Typically, the body-area determinations that can be made are head hairs (from the scalp), pubic hairs, facial hairs (beard and mustache), limb hairs (arm/leg), chest hairs, axillary hairs (armpit), and eyebrow/eyelash hairs. However, hairs may be encountered that cannot be categorized into one of these groups. These may consist of "transitional" hairs, that is, those hairs growing between two body regions, hair fragments that are not large enough to be identified, or hairs from other body areas.

Once the race and body-area determinations have been made, the suitability for comparison is determined. Hairs that have been characterized as head hairs or pubic hairs are generally considered suitable for comparison with a known head-hair or pubic-hair sample. Hairs from other body areas generally are not considered suitable for comparison because these other body-area hairs generally do not contain sufficient variation in their microscopic characteristics to reliably distinguish between hairs from different individuals. In limited circumstances and with limited significance ascribed to an association, a microscopic comparison may be conducted between these other body-area hairs and an appropriate known sample. However, the limitations of these comparisons must be understood by the hair examiner and conveyed in a report.

Once a hair has been determined to be suitable for microscopic comparison, it is compared with an appropriate known hair sample. Head hairs must be compared with known head-hair samples, and pubic hairs must be compared to known pubic-hair samples.

The comparison process involves the side-by-side analysis of a questioned hair and known hair samples using a comparison microscope. This allows for a direct comparison of the microscopic characteristics of the questioned hair within the same relative area of the known sample, at the same time and in the same field of view. This comparison must occur over the entire length of the hair.

In 1982, an ad-hoc Committee on Forensic Hair Comparisons was formed with Barry Gaudette as the chairman. This committee represented 10 U.S. states, Canada, and Great Britain laboratories and included representatives from law enforcement laboratories, private laboratories, academic institutions, and the National Bureau of Standards. This group of highly qualified hair examiners met to advance forensic hair comparison as a science (as cited in Federal Bureau of Investigation [FBI] 1985).

After two meetings, the committee published its recommendations in the following seven areas:

Terminology definition and standardization.

Establishment of a protocol for microscopical human-hair comparison.

Investigation and standardization of macroscopic and microscopic hair comparison characteristics.

Conclusion, report writing, and court testimony in forensic hair comparison.

Training of hair examiners.

Quality assurance in forensic hair comparison.

Nonmicroscopical methods of forensic hair comparison. (as cited in FBI 1985)

These meetings were followed in 1985 by an International Symposium on Forensic Hair Comparisons.

The Committee on Forensic Hair Comparison recommended using a comparison microscope, stating that the hair examiner must use a high-quality comparison microscope at different magnifications to conduct a thorough and careful examination of both the gross and microscopic characteristics exhibited by properly prepared hairs (as cited in FBI 1985). Robertson (1999) also expressed the opinion that the microscopic comparison of hairs cannot be conducted without a comparison microscope.

The Scientific Working Group on Materials Analysis (SWGMAT), which evolved from the original Committee on Forensic Hair Comparison, has one of its subgroups dedicated to forensic hair comparisons. SWGMAT states that the use of a high-quality transmitted light microscope is necessary to examine and identify the microscopic characteristics of hairs (SWGMAT 2005).

A number of authors have published examination procedures for the forensic examination of hair, including the Committee on Forensic Hair Comparison (as cited in FBI 1985), Robertson (1999), Shaffer (1982), Strauss (1983), and SWGMAT (2005). According to the SWGMAT guidelines (2005), in order to conclude that a questioned hair and a known sample are consistent with sharing a common origin (association), it must be determined that there are no significant differences between the two. In other words, for a conclusion of an association to be made, it must be determined that the characteristics exhibited by the questioned sample are represented in the known sample.

The starting point in a forensic hair examination must be an attempt to look for differences, not similarities, between a questioned hair and a known sample (Robertson 1999). Even within an individual, the expectation must be that a known sample will exhibit a range of microscopic characteristics. Because hairs are a biological product and there are both genotypic and phenotypic influences on the arrangement of their microscopic characteristics, no two hairs, even from the same person, can look exactly alike. Therefore, even when an association is made, it does not mean that the questioned hair and a single hair from the known sample will be identical in all features along the entire length of the hairs.

The assessment of what is or is not a meaningful or significant difference lies at the core of the training and experience of the forensic hair examiner. These examinations should be conducted only by a properly trained hair examiner employing a side-by-side comparison of a questioned hair and a known sample.

Three general conclusions can be reached as a result of microscopic hair analysis: exclusion, no conclusion, or association. Within the categories of exclusion and association, there are two subcategories (see Gaudette 1985). When a questioned hair (a hair of unknown origin) is compared with a known hair sample (a sample of hairs removed from a particular body area of a person) and differences in the observed microscopic characteristics are found, the hair examiner can conclude that the questioned hair is not consistent with originating from the source or donor of the known hair sample.

Is it possible to definitively exclude an evidence sample as originating from a particular donor based on microscopic hair comparisons? Stating categorically that a questioned hair definitely did not come from the donor of a known sample implies that the probability of an incorrect exclusion is zero (or so small to be effectively zero). Some possible causes of an incorrect exclusion are examiner error, too few reference hairs comprising the known sample, the known sample is not representative of the body region, incomplete hairs in the known sample, a large amount of time between the deposition of the questioned hair and the collection of the known sample, and the possibility that the questioned sample is an atypical hair. If an examiner is properly trained and follows appropriate procedures, then the probability of an incorrect exclusion based on these possible scenarios is minimal.

Regardless, a hair examiner is limited when providing an interpretation that the hair definitely did not come from a particular person (as an examiner would be if he or she were to state that the hair definitely came from a particular person-an almost impossible conclusion given the limitations of the evidence and/or technology). Although a false exclusion is not as serious as a false inclusion, there are still consequences associated with a false exclusion.

For example, an examiner can state that the questioned hair (a short, colorless [gray] hair) is not consistent with originating from the suspect, but the number of gray hairs on the suspect's scalp was so few that they were not represented in the known sample. A categorical exclusion in this case might direct an investigation in an improper course.

There are few circumstances in which an absolute exclusion can be rendered, such as when the questioned hair and the known hair samples exhibit different racial characteristics. In this scenario, the examiner may be able to conclude that "the questioned hair is microscopically dissimilar to hairs in the known hair sample and therefore could not have come from the donor of the known hair sample."

The scenario of the gray-hair exclusion cited above, however, would not meet any of these potential exclusion circumstances. The examiner would have to conclude that "the questioned hair is microscopically dissimilar to the hairs in the known hair sample, and the questioned hair is not consistent with originating from the source of the known sample." Although the characteristics of the questioned hair may not encompass the range of characteristics exhibited by the known hair sample, a low percentage of gray hairs may not be seen simply because of sampling error. The great majority of microscopic hair exclusions have similar limitations.

When a significant difference is observed between a questioned hair and a known hair sample, then it must be concluded that the questioned hair and the known hair sample are not consistent with sharing a common origin. More precisely, the hair is not consistent with originating from the donor of the known sample as represented by the hairs present in the known sample.

Another category of conclusion that can be reached by a microscopic-hair examiner is that "no conclusion" can be reached as to whether or not the questioned hair is consistent with originating from the donor of the known sample. This conclusion is reserved for circumstances when the questioned hair exhibits similarities to the hairs in the known sample but also exhibits some slight microscopic differences; however, these differences are not sufficient to conclude that the hair is not consistent with originating from the donor of the known sample. Some possible causes for these slight differences are (1) a significant amount of time has occurred between the deposition of the questioned hair and the collection of the known sample (typically more than one year); (2) the questioned hair is significantly longer (or shorter) than the hairs in the known head-hair sample (for example, the donor of the known sample may have cut his or her hair after deposition of the questioned hair); (3) the questioned hair has not been artificially treated, but the known sample has been; (4) the questioned hair is not a full-length hair; that is, a portion(s) of the hair is/are missing; (5) the known sample contains too few hairs for an adequate comparison; and (6) the questioned hair comes from a different donor.

The typical wording for a "no conclusion" is: "The questioned hair exhibits similarities and slight microscopic differences, and therefore, no conclusion can be reached as to whether or not the questioned hair is consistent with originating from the donor of the known hair sample." When this conclusion is reached, these hairs may be submitted for mitochondrial DNA (mtDNA) analysis.

The final category of conclusion that can be reached in a microscopic hair comparison is that of an association. In contrast to the two subcategories of an exclusion result, there is only one conclusion for association, that the questioned hair exhibits the same microscopic characteristics as the hairs in the known hair sample and therefore cannot be excluded from originating from the source of the known sample. It is possible to contrive a scenario where one might logically report a strong positive association, that is, state that the questioned hair originated from the donor of the known hair sample.

For example, if one knew that the person with the longest hair in the world had hair that was 26 feet long and if a 26-foot-long hair was recovered from a crime scene that exhibited all of the same microscopic characteristics as the hairs in the known hair sample, it would be possible to state that the hair definitely came from that person. However, the likelihood of such an event occurring is so rare that it is not meaningful.

When an association is made, the conclusion would be stated as follows: "The questioned hair exhibits the same microscopic characteristics as the hairs in the known hair sample, and accordingly, the questioned hair is consistent with originating from the same source as the known sample." This means that all of the microscopic characteristics expressed by the questioned hair are represented within the range of characteristics exhibited by the known hair sample. In other words, no significant differences can be found.

The final step of a hair examination should be a verification or confirmation procedure. This step involves having a second qualified examiner conduct an independent microscopic comparison of the hair that has been associated (SWGMAT 2005). The second examiner must conduct a thorough, complete analysis and must be free to reach his or her own conclusion on each hair. Only upon the second examiner's reaching agreement should a microscopic hair association be reported. In accordance with FBI Laboratory standard operating procedures, when this conclusion is reached, these hairs are submitted for mtDNA analysis.

Not all conclusions of a hair association can be weighted equally. Consider the following two examples. First, a questioned hair is recovered from a hat that was found on the side of the road and believed to be used in a bank robbery. Microscopic examination reveals that the hair is a blond, Caucasian head hair. Comparison with known hair samples from suspects in a bank robbery results in the questioned hair's being associated with one of the suspects and excluded from the other two suspects.

Second, a questioned hair is recovered from the backseat of a vehicle used to transport the victim of a kidnapping. Microscopic examination reveals that the hair is a long, dark brown, Caucasian head hair that exhibits characteristics of being artificially treated three separate times over the length of the hair. Comparison with known hair samples from the victim and persons that were known or suspected to be in the car results in the questioned hair's being associated with the victim and excluded from the persons known or suspected to have been in the car.

In these two scenarios, more relative weight can be ascribed to the hair association in the second scenario, because additional characteristics are present for comparison, namely the artificial treatment (dark brown color) and the length of the hair. Because there is no known mechanism for a hair examiner to quantitatively assess the additional weight of these special characteristics, it is incumbent upon the hair examiner to explain this to the trier of fact. Fact finders, from their own experiences, can assess the significance of the results conveyed by the hair examiner.

Most important, when conducting hair examinations, properly trained and qualified examiners would not and should not opine that a hair could be attributed to an individual to the exclusion of all others. This basic tenet of the science has been espoused since the inception of the discipline (as first described by Rudolf Virchow in 1861; cited in Bisbing 1982). The hair examiner must convey, both in the written report and in courtroom testimony, the limitations of the science and, especially, an interpretation of an association.

In order to ensure that proper weight is put on the results and interpretation of a microscopic hair comparison, FBI Laboratory reports for the past 40 years have stated that hair comparisons are not a means of individualization in reports of examination containing microscopic hair comparisons. In addition, FBI hair examiners are trained to include, at a minimum, the same information during their testimony on cases involving a hair association.

Not only must fact finders be aware of the conclusion reached by the examiner, they also must be aware of the limitations of the science so they can properly appreciate the significance of a result. Providing an explanation of the results will best overcome possible confusion from similar but differently phrased conclusions such as "is consistent with" or "could have come from." Regardless of the phraseology used, the fact finder must be given supporting information beyond the statement of an association.

Some critics emphasize the fact that microscopic-hair examiners are unable to statistically quantify the significance of an association (see, for example, Robertson 1999). The development of a statistical model would involve frequency data across the entire population for all microscopic characteristics present in hair. Although this is an attractive idea, the difficulties associated with generating such a database have been, to date, practically insurmountable. In order to generate frequency data for hair characteristics, microscopic-hair examiners might be required to use a "checklist" or "archetype" approach rather than the pattern-recognition process normally used.

However, two hairs that may be "alike" based on a checklist may very well be microscopically different (see Gaudette and Keeping 1974; Strauss 1983). In addition, different examiners are likely to describe hairs in different ways (see Gaudette and Keeping 1974; Podolak and Blythe 1985). Finally, the same examiner may vary his or her description of the same hair on different days (see Wickenheiser and Hepworth 1990).

These examples do not reflect a flaw in the science of microscopic hair comparisons or an error by a microscopic-hair examiner; rather, they serve to highlight the limitations of generating a useful database. The database approach confines the examiner to documenting the status of single characteristics at a specific location in a single focal plane as opposed to a holistic approach. That characteristic may change slightly at a different focal plane even at the exact same location and may change dramatically at a different location in the hair. In a single hair, there are hundreds or even thousands of possible different fields of view.

It has been pointed out previously (see Wickenheiser and Hepworth 1990) that this classification method would force the examiner to choose, subjectively, from the myriad possible fields of view, the one that best represents that characteristic. This subjective choice then must be repeated for all of the remaining microscopic characteristics present in hair. Because of the inherent variation in the microscopic characteristics of hair, the use of such an approach likely would result in a situation where two hairs that "match" according to the checklist in reality look nothing alike.

Given that useful statistical data are not generated regarding the relative frequency of an evidentiary hair, one must accept that the answer to the question, what proportion of the population would have characteristics that are the same as the evidentiary hair? is we do not know. Similarly, the answer to the question, what is the probability of a coincidental match between the questioned hair and the known sample? is we do not know. Rather, the fundamental question that can be addressed is, what is the value of the evidence in establishing the association? (see Gaudette 1986). Numerous empirical studies exist detailing the ability of microscopic hair comparisons to reach the correct conclusion; these empirical studies can provide some guidance on the significance of an association.

Numerous studies have been conducted that support the science of microscopic hair comparisons. Strauss (1983) conducted a study using 100 individuals comprising 54 Caucasian, 19 Negroid, and 27 Mongoloid. From each of the 100 individuals, 7 hairs were chosen to represent the widest variation possible. These were mounted on glass microscope slides and were designated as the known samples. One hair was also chosen from each of the 100 samples, mounted on glass microscope slides, and designated as questioned hair samples. All 800 hairs (700 known hairs and 100 questioned hairs) were individually characterized using a checklist and punch cards.

A series of seven experiments was conducted. A neutral party selected a total of 10 single questioned hairs to be compared with 10 known samples. Comparison microscopy resulted in 100 percent accuracy in associating the correct questioned hair with its known source, showing that they could reliably associate a questioned hair with a known sample. In addition, the study showed that the examiners correctly identified each of the 100 individuals in the questioned hair pool to the correct known hair group, that is, 54 Caucasian, 19 Negroid, and 27 Mongoloid.

Gaudette and Keeping (1974) obtained head-hair samples from 100 individuals. Within the group, 92 were Caucasian, 6 were Mongoloid, and 2 were Negroid hairs. From each of these samples, 6 to 11 macroscopically dissimilar hairs were selected to represent the range of microscopic characteristics present in the known sample. These hairs were then mounted individually on glass microscope slides. The hairs were characterized, and the microscopic characteristics were categorized using punch cards. Each hole in the punch card was associated with a specific microscopic characteristic. The cards from each individual were combined with all of the others and were sorted based on similar holes in the punch cards. The hairs for each of these similar cards were then compared microscopically. Using this system, a total of 861 hairs from 100 different individuals were examined and compared, for a total of 370,230 comparisons. From all of these comparisons, only 9 pairs of hairs were found to be indistinguishable.

In a similar study, Gaudette (1976) obtained 30 pulled pubic hairs from 60 different individuals. All of these were Caucasian hairs. From these, 6 to 11 dissimilar hairs were selected randomly to represent the range of characteristics present in the 30 hairs. As in the previous study, the characteristics were coded on punch cards, and the cards were combined and sorted. With the 454 hairs, the total number of comparisons made was 102,831. A total of 16 pairs of hairs were found to be indistinguishable.

From each of these studies, the authors attempted to obtain probability estimates for head-hair and pubic-hair comparisons. The probability estimates proposed by Gaudette and Keeping (1974) and Gaudette (1976) for the frequency of head and pubic hairs cannot apply to the population at large. The probabilities they derived refer to the process of distinguishing between two hairs that the examiner knew originated from different people. In addition, the authors found that different examiners obtained different results in the single-hair comparison study. This would mean that even if the data were correct, the probability estimate would have to be generated by each new person using the technique. This is not comparable to the normal casework scenario for a microscopic-hair examiner, where a questioned hair is compared to known hair samples (Barnett and Ogle 1982). In a later paper, Gaudette (1978) stated that "the significance of this research is not in the actual probability numbers found but in experimental proof of the proposition that macroscopic and microscopic hair comparison is a useful technique and that hair evidence is good evidence" (Gaudette 1978).

In the same study (1978), Gaudette provided each of three examiner trainees with one separate known head-hair sample, consisting of 80 scalp hairs. Each of the trainees was then given 100 questioned hairs from different individuals, one of which was the one represented by the known standard. Without being told how many individuals the unknowns were from or how many, if any, of the hairs were supposed to be similar to the standard, the trainees were instructed to compare the questioned hairs with the known standards and report their results. Two of the trainees correctly identified one and only one hair with the known standard.

The third trainee initially concluded that there were four hairs similar to the standard. However, upon further examination and consultation with other examiners, he was able to eliminate one of the four. However, he still concluded that the three remaining hairs could not be eliminated: the correct one and two others. All of the hairs that remained were of the common, featureless type.

Another experienced examiner evaluated the three remaining hairs and concluded that the correct hair could not be eliminated and, in addition, that one of the two others could not be eliminated. Yet another examiner looked at the remaining three hairs and agreed that the correct hair could not be eliminated and, in addition, that the other of the remaining two could not be eliminated.

Another experiment was conducted, again using 100 representative scalp hairs from 100 individuals. From these, one sample was selected. From this sample, a single hair was then selected at random. Thus, there was one questioned hair that was compared with 100 known standards. This experiment was then repeated. On both occasions, it was found that the unknown hair could be associated with one and only one standard-the correct one.

In a third experiment, the unknown hair was chosen specifically to be a common, featureless hair. This hair was found to be similar to two standards: the correct one and one additional one.

Based on these series of experiments, Gaudette found that when an experienced hair examiner conducts a hair comparison using all of the available microscopic characteristics, these comparisons were reliable and repeatable. He also offered that special training in hair comparison of at least a year in length is required to enable a person to develop the required level of discrimination.

Wickenheiser and Hepworth (1990) obtained head-hair samples from 97 different individuals, including a number of closely related individuals from several generations. Between 5 and 13 dissimilar hairs from each sample were chosen to represent the range of characteristics in the known sample. These were numbered randomly by an independent party. In addition, 53 additional hairs randomly chosen from the original 97 known samples were also numbered randomly. In total, 930 hairs were selected and placed on glass microscope slides. All of these hairs were examined to determine how many matching pairs were present. Each hair was compared to all of the other 929 hairs, for a total of 431,985 hair comparisons.

Two different examiners developed comparison checklists and used a computer program to sort the hairs based on these checklists. As a result of the computer sorting based on gross macroscopic and microscopic characteristics, the first examiner conducted 749 one-to-one microscopic comparisons, and the second examiner conducted 2006 comparisons. The first examiner found seven pairs of hairs that were microscopically indistinguishable, and the second examiner found six pairs. In every case where a one-to-one association was found, the hairs were truly from the same source. No incorrect associations were made by either examiner. Based on their findings, the authors determined that if a one-to-one match is the requirement in a microscopic hair comparison, then the incidence for an error is very low.

Bisbing and Wolner (1984) conducted a series of studies using known head-hair samples recovered from 17 sets of twins and 1 set of identical triplets. Of the twins included in the study, 9 were fraternal twins, 6 were identical twins, and 2 were of unknown zygosity. All of the twins were Caucasian, and 11 of the 18 sets were blond. In addition, all of the samples were cut. The authors commented that the predominance of blond hair and the absence of hair roots made these comparisons unusually difficult. In fact, many of the samples were considered by the authors to be common, featureless hairs.

From each of the individuals in the study, two known hair samples were mounted on glass microscope slides and were assigned a random number. This resulted in a total of 74 known samples. The authors then conducted comparisons of each twin sample with all other samples. By visual and microscopic examination, both authors were able to correctly distinguish all of the known samples and were able to accurately associate the duplicate samples with each other. The specimens were never incorrectly associated, even with the known hair sample of the twin.

In order to more closely resemble true forensic casework, a second study was conducted. This study involved removing 2 or 3 hairs from 7 randomly selected unmounted samples, which were then mounted on glass microscope slides. For each of these 7 "questioned" samples, between 5 and 10 known samples were randomly selected from the 74 mounted known samples for microscopic comparison. There were 52 comparisons made by each of the two examiners, for a total of 104 comparisons. Because of the random sampling, none of the true known samples for the questioned hairs was present in any of the comparison scenarios. The two examiners correctly excluded 96 of the known samples as being possible donors of the questioned hairs. Eight of the questioned hair samples were incorrectly associated to the known samples (5 by one examiner and 3 by the second examiner). In one of these cases, a sample of the fraternal twin's hair was present in the known pool and was correctly eliminated. In the other simulated cases, the questioned hairs were incorrectly associated with control samples that were neither the true source nor the twin of the true source.

It is interesting to note that 7 of the 8 incorrectly associated hairs were classified by the authors as being blond, common, featureless hairs. These results serve to reinforce that human hair cannot be associated with one person to the exclusion of all others. In addition, this study served to show that caution is necessary when comparing common, featureless hairs. Finally, the authors stated that the verification process might measurably reduce the possibility of Type II errors.

Suzanski (1988) conducted a blind study involving comparison of 15 questioned hairs with known hair samples obtained from 25 purebred German shepherd dogs. He made no false inclusions and correctly assigned 6 of the 15 questioned hairs to their known sample of origin. In a later study (1989), Suzanski compared 25 questioned hair samples of approximately 10 hairs each with known samples from 100 mixed-breed and purebred dogs. He was able to assign all 25 of the questioned hair samples to the known samples, with no incorrect associations.

From these studies, we can conclude that microscopic hair comparisons are reliable and are indeed a valid scientific method. If a properly trained hair examiner uses a valid procedure, the examiner can achieve the correct result. It is important to note that hairs are not a means of personal identification, and this information must be conveyed both in a written report and during testimony. It is acknowledged that the microscopic characteristics exhibited by a questioned hair can be encompassed by the range of characteristics exhibited by more than one person. However, if an examiner associates a questioned hair with a known sample that is known to be from a different person, it does not imply an error or a mistake on the part of the microscopic-hair examiner. Rather, it highlights the limitations of the science.

For the past 100 years, microscopic hair comparisons have been the only method available to determine if an association exists between two people or between a person and an object based on hairs recovered from evidentiary items. These comparisons have been routinely conducted in forensic laboratories and accepted both in the scientific community and in the legal community for the past 75 years. Because of the limits of the science of microscopic hair comparison, the strongest conclusion that a microscopic-hair examiner can ever make is that a hair "is consistent with" or "could have come from" the donor of the known sample. However, the studies cited above do show that the method is reliable and repeatable. In addition, these studies demonstrate both the exclusionary and a degree of inclusionary power of microscopic hair comparison.

A wealth of information can be gained from the microscopic analysis and comparison of hairs-information that may be crucial to a case, such as the ability to exclude persons who are not the source of an evidence hair. Fortunately, another tool is available to augment microscopic hair analysis. With the advent of DNA testing, both nuclear and mitochondrial, an additional, independent examination is available to compare the questioned hair and the donor of the known hair sample.

The tools of molecular biology have enabled forensic scientists to characterize biological evidence at the DNA level, both nuclear and mtDNA. Any material, including hair, that contains nucleated cells can potentially be exploited using nuclear DNA typing. Typically, these hairs must contain sheath material for nuclear DNA typing to be successful. When this material is found, nuclear DNA testing is the best, most discriminating technique available for the comparison of a questioned hair with a known sample. No other technique in the field of hair comparison can result in the potential individualization of the questioned hair to a known source. When a questioned hair can be microscopically associated with a known sample and sufficient root material is present, this hair should be subjected to nuclear DNA analysis.

Kolowski et al. (2004) conducted a study to evaluate the accuracy of short tandem repeat (STR) DNA analysis and microscopic comparison. Pubic-hair samples consisting of at least 50 hairs were collected from 27 volunteers employed in their laboratory. Laboratory volunteers were used because each employee's DNA was present in a laboratory database. From these samples, a neutral third party created five sets of four hairs each to act as questioned hair samples. Of each of these samples, two of the hairs had to be in the anagen, or actively growing, phase. For the known hair samples, five hairs were selected and mounted on glass microscope slides. The root end of each of the two anagen hairs from each sample was cut, the nuclear DNA was extracted, and this extract was analyzed using STR typing technology. The remaining portion of these two hairs as well as the two remaining hairs from the questioned hair samples were then compared microscopically with five of the hairs selected from the known pubic-hair samples according to SWGMAT guidelines (2005).

Short tandem repeat typing of the unknown hair samples correctly identified the source of three of the questioned hair samples. Of the two remaining hair samples, one could not be DNA-typed using either of the questioned hairs in the sample, and therefore, no conclusion could be reached. On the final questioned hair sample, no DNA profile was obtained from the first hair, and only a partial profile could be obtained from the second hair. Because it was only a partial profile, the profile could be attributed to two people present in the laboratory staff database. Overall, STR analysis was able to identify only three out of five unknown hairs with their known source. The microscopic hair analysis was able to associate four of the five questioned hair samples with their source. One of the five questioned hair samples was incorrectly associated with the incorrect source by microscopic analysis.

The authors noted that the questioned hairs in this set were very small and would not normally have been analyzed in normal casework. In addition to the small size of the hairs in the questioned hair sample incorrectly associated with a known, it is also important to note that the authors did not mention whether or not a microscopic verification was conducted by an independent examiner. The addition of the verification step may very well have detected the incorrectly associated questioned hair. Also, the authors used only five hairs from each known sample for the microscopic comparison process. This also may have contributed to the incorrectly associated questioned hair sample. SWGMAT guidelines suggest collecting 25 pubic hairs in a pubic-hair known sample and 50 hairs in a known head-hair sample.

Although nuclear DNA analysis is a powerful individualizing tool, it does not lend itself well to screening through a tremendous volume of evidence to identify hairs of interest. Microscopic analysis is better suited to distinguishing between a hair or a textile fiber, an animal hair or a human hair, a head hair or a pubic hair, a Caucasian hair or a Mongoloid hair, and a forcibly removed hair or a naturally shed hair. Microscopic examination also may contribute contextual information regarding the hair in question that may be critically important to the case.

For example, in a case where a husband is accused of bludgeoning his wife with a hammer, finding a hair on the hammer that can be microscopically associated with the victim would likely be of limited significance. However, if the hair also exhibits microscopic characteristics of being crushed or damaged, the significance of the association increases greatly. Similarly, finding hairs that can be microscopically associated with a victim in the trunk of her spouse's car would not be unusual unless these hairs also exhibited signs of decomposition, showing that they were deposited sometime after the victim's death.

One of the limiting factors with performing STR analysis on hairs recovered in casework rests in the fact that most of the hairs encountered are shed naturally and contain little nuclear DNA-containing tissue. Naturally shed hairs typically do not provide sufficient amounts of nuclear DNA for analysis. In contrast, the vast majority of these hairs have ample amounts of mtDNA present. Because a cell can contain more than 5000 copies of mtDNA (Bogenhagen and Clayton 1974), this analysis is currently the best approach to the genetic typing of these hairs (DiZinno et al. 1999). The guidelines for this analysis with respect to routine forensic casework were first outlined in Wilson et al. (1993).

Unlike nuclear DNA, mtDNA is maternally inherited (Case and Wallace 1981; Giles et al. 1980; Hutchinson et al. 1974) and is not unique to an individual. Therefore, mtDNA, much like the microscopic analysis of hair, cannot be used to positively identify an individual, but it can be used to exclude a potentially large portion of the population as a possible donor of the hair.

Houck and Budowle (2002) reviewed 170 human hairs submitted to the FBI Laboratory and subjected to both microscopic and mtDNA analysis between 1996 and 2000. The results of the microscopic human-hair comparison were placed in four different categories: a positive association (i.e., cannot exclude); a negative association (i.e., can exclude); an inconclusive result (i.e., cannot render an opinion); or no examination (i.e., insufficient or unsuitable sample to attempt an examination). The results of the mtDNA analysis were placed in four similar categories: concordant (or inclusion), inconclusive, exclusion, or insufficient DNA to reach a conclusion.

Of the 80 hairs that were associated using microscopic hair comparisons, 69 were consistent with mtDNA analysis, 1 was inconclusive, 9 were excluded, and 1 had insufficient mtDNA present. Excluding the inconclusive and insufficient mtDNA results yields agreement between the microscopic and mtDNA hair analysis more than 88 percent of the time. Four of the 9 hairs excluded by mtDNA analysis were categorized microscopically as being blond in color. Blond hairs, as discussed previously, have fewer microscopic characteristics available for use in the microscopic comparison process.

These nine mtDNA exclusions cannot be used as an error rate for the microscopic comparison method; rather, they demonstrate the limitation of the resolving power of microscopic comparison of the hairs examined in this study. There were no known mistakes made in the microscopic hair or mtDNA analyses. Although the mtDNA analysis did exclude the donor of the known sample as the source of the questioned hair, it does not mean that the microscopic characteristics of the questioned hair were different than those of the known sample. It does not imply a mistake on the part of the science or the microscopic-hair examiner. As explained previously, microscopic hair comparisons are not the basis for personal identification, and some people will share similar hair morphological characteristics.

Imagine the following scenario: Two brothers are both suspects in a case, and one is the true donor of a hair found at the crime scene. Both of the brothers will have the same mtDNA sequence, and therefore, mtDNA analysis would not be able to exclude a questioned hair as having come from either brother. However, microscopic analysis may be able to exclude one brother and not exclude the other brother as the donor of the hair. This does not imply an error on the part of the mtDNA analysis or the mtDNA examiner but rather identifies the limitation of the technology. Both of the techniques have value when their application is understood.

In Houck and Budowle (2002), there were no apparent differences in the exclusions obtained by either method. Of the 19 hairs excluded by microscopic comparison, 17 were confirmed, and the remaining 2 were either inconclusive or insufficient by mtDNA analysis. Of the 71 hairs that were either inconclusive or where no microscopic examination was conducted (that is, when the hairs were categorized as not suitable for comparison with a known sample), mtDNA analysis was able to give a definitive result of either association or exclusion on 66 of the hairs. Therefore, when an important evidentiary hair recovered from the crime scene cannot be microscopically compared, mtDNA analysis should be sought when possible.

In summary, a combination of microscopic examination of hairs followed by DNA examination (either nuclear or mtDNA) will yield the best possible information on the evidentiary questioned hairs. Because of the destructive nature of both DNA techniques, the microscopic analysis must be conducted first, followed by the DNA examination, because that portion of the hair used in the DNA analysis will be destroyed, making it unavailable for the microscopic examination.

The primary challenge of microscopic hair analysis is in the biological variation of microscopic characteristics that exists within the hairs from a single individual. This is further compounded by the fact that variation exists even along the shaft of a single hair (Gaudette 1978). It is generally accepted within the forensic science community that hairs are not a means of positive identification, but they can provide substantial information because of the variation in hair among individuals.

Also, if a questioned hair and a known sample are significantly different, they can be positively excluded as having come from a common source (such as differences in racial identification). Frequency data for the myriad observable microscopic characteristics are not available (Ogle 1998; Robertson 1982; Robertson and Aitken 1986), and a method for properly combining these features has not yet been produced. Therefore the significance of their occurrence within a single sample cannot be expressed and compared numerically (Kind and Owen 1976). It must be done qualitatively or semiqualitatively.

When a questioned hair is associated with a known sample, there is no accepted number of characteristics that must be similar between the two known samples. Rather, it is generally accepted that all of the characteristics exhibited by the evidentiary hair must be represented by the hairs in the known hair sample in order to support a conclusion of association. Jones (1956) stated: "The probability of identity may grow with every point of resemblance and with the number of hairs available for comparison, but that probability should never be stated as a certainty."

The limitation of the science is that there is always the possibility of a coincidental match. The possibility of this event should not be construed as an error. Simply put, some people can share the same microscopic characteristics.

One should not construe that a probability statement equates to reliability. Simply because the statistical probability of hair evidence cannot be calculated does not make the comparison unreliable. To ensure proper weighting of an association, it is essential that the limitations of microscopic hair comparisons be understood by the examiner and conveyed to all interested parties.

Houck and Budowle (2002) stressed that microscopic hair comparisons are not a "screening test" and mtDNA analysis is not a "confirmatory test." The combination of the two methods (microscopic hair comparison coupled with either nuclear DNA or mtDNA analysis) provides the judicial system with significantly more powerful information than either method does alone. Yet each technique on its own is useful.

At many crime scenes, hairs may be the most common trace material recovered. In fact, hairs may be the only forensic evidence available. Often, the condition of these hairs may be an important factor in determining their "history," such as the presence of damaged hairs on a murder weapon or in the known sample from the victim. To ignore them limits the proper analysis of the crime scene and may leave very important questions unanswered.

Robertson (1999) stated that the greatest danger is to have hair examinations conducted by generalists who lack proper training and competence. This author agrees. Some of the greatest disservices to the field of microscopic hair comparison have been contributed by those lacking the necessary training, experience, and ability to properly explain the process, limitations, meaning, and significance of a microscopic hair association.

Crocker (1991) stated that "the greatest challenge faced by forensic hair examiners is to be able to leave the witness box with a feeling of assurance that members of a jury, or a judge acting alone, have the same appreciation as the examiner does of the proper level of significance to be given to the hair evidence." It is the responsibility of the examiner to clearly state, both in the report and in any testimony, the limitations of the science of forensic hair examinations as well as the significance or weight of an association or exclusion.

Because of the importance of experience in the field of microscopic hair analysis and comparison, it is critical that personnel undertaking these examinations spend a considerable amount of their time conducting these examinations. One cannot expect an examiner to conduct these examinations part-time, remain technically competent, and be able to provide reliable results. Robertson (1999) made an excellent point when he stated:

It is also time for laboratory systems and scientists that are either unable or unwilling to embrace hair examinations with the necessary investment in time and commitment to withdraw altogether from the field. Half-hearted commitment can only continue to do damage to the credibility of hair examination. (Robertson 1999)

Guidelines have been established by SWGMAT for the forensic examination of hair. This consensus document produced by representatives of the microscopic-hair examination community describes:

Procedures for microscopic examination of hair.

Recommended instrumentation.

Integration of the microscopic examination and DNA analysis of hair.

Documentation and report writing.

Interpretation and testimony.

Quality assurance and proficiency testing. (SWGMAT 2005)

It is imperative that any examiner practicing the science of microscopic hair comparison adhere to a guideline such as this. In addition, there is no substitute for a well-documented, rigorous training program in the microscopic examination and comparison of hair. Given these conditions, forensic hair comparison can provide reliable, scientifically valid, and important information in a criminal investigation.

This is publication number 09-03 of the Laboratory Division of the Federal Bureau of Investigation. Names of commercial manufacturers are provided for identification only, and inclusion does not imply endorsement by the FBI.

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Review Article - Forensic Hair Comparison: Background Information for Interpretation - April 2009

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April 2009 - Volume 11 - Number 2 Introduction | Scientific Basis for Microscopic Hair Examinations | Microscopic Characteristics-Hair Identification Transfer and Persistence of Hairs | Hair-Collection Process | Race and Body-Area Identification | Procedure for Microscopic Hair Comparisons | Studies Supporting Microscopic Hair Comparison | DNA Analysis of Hairs | Conclusions | Acknowledgment | References Hair evidence is one of the most common types of evidence encountered in criminal investigations.

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https://losangeles.cbslocal.com/2010/08/31/1977-cold-case-murder-solved-by-a-hair/

Gavyn Fountain

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/ KCAL News

RUBIDOUX (CBS 2) - The case is worthy of any "Cold Case" story shown on TV. Riverside County sheriff's homicide detectives announced Tuesday that they have solved the 1977 murder of a Rubidoux bartender.

Hair found clenched in the victim's hand was recently sent to a private laboratory in Texas for DNA testing, a sheriff's sergeant said.

The DNA test showed that the hair belonged to Frank Wright, who died in 2002 from complications related to alcohol abuse, said Sgt. Scott Brown of the Riverside County sheriff's Central Homicide Unit.

James Anagnos, who was known as "Jimmy the Greek," was found dead Oct. 18, 1977 inside his bar at closing time, Brown said.

Anagnos was stabbed 20 times with a steak knife and had been hit four times in the head with a blunt object, Brown said, adding that the cause of death was from injuries to his head.

The hair was found clenched in Anagnos hand, and was believed to have come from the suspect, but the laboratory at the time was not able to match the hair samples to Wright who was 50 at the time of his death.

Wright was identified as a suspect when detectives learned he was involved in an argument with Anagnos about an hour before the bar's closing, according to Brown.

There were no independent witnesses to the attack, so the District Attorney's Office did not file charges against Wright, Brown said.

The hair was sent earlier this year to Orchid Cellmark, a private lab in Texas, for testing, he said.

The DNA test confirmed the hair found in Anagnos' hand belonged to Wright, according to Brown.

This was the third case solved by the Cold Case Unit since being awarded a grant by the National Institute of Justice.

The sheriff's Cold Case Unit is examining more than 70 unsolved cases that may have DNA evidence, Brown said.
©2010 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Wire services contributed to this report.)

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KCAL News RUBIDOUX (CBS 2) - The case is worthy of any "Cold Case" story shown on TV. Riverside County sheriff's homicide detectives announced Tuesday that they have solved the 1977 murder of a Rubidoux bartender. Hair found clenched in the victim's hand was recently sent to a private laboratory in Texas for DNA testing, a sheriff's sergeant said.

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Home > 3. Evidence Collection > Hair and Fiber

The most common methods used to collect hair and fiber evidence include the following:

Visual collection. On some surfaces, hairs and fibers can be seen with the naked eye. Through use of clean forceps and paper (i.e., trace paper), the sample can be removed from the surface and placed into a clean piece of paper that can be folded and packaged in a paper envelope.

Tape lifting. Trace tapes are available for the collection of trace hair and fiber evidence. The tape is applied to the location of the suspected sample, removed and packaged.

Vacuuming. The area where the suspected samples are located is vacuumed and evidence is caught in a filtered trap attached to the vacuum. These samples are packaged in clean trace paper for submission to the laboratory. Vacuuming is the least desirable collection method because there is a risk of cross-contamination if the equipment is not properly cleaned between each use.

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Home > 3. Evidence Collection > Hair and Fiber The most common methods used to collect hair and fiber evidence include the following: Visual collection. On some surfaces, hairs and fibers can be seen with the naked eye.

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tweezers or adhesive tape to collect hair evidence. ABarrow

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Hairs, Fibers, Crime, and Evidence | Office of Justice Programs

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May 21, 2003 -- On the day she was abducted, 16-year-old Sofia Silva was sitting on her front porch in Spotsylvania, Va., doing homework. It was Sept. 9, 1996.

Five weeks later, investigators found her body in a nearby creek.

Eight months later, it happened again, in the same town, just 70 miles south of Washington, D.C. After getting off separate school buses near their home, Kati and Kristin Lisk disappeared. The bodies of the 12- and 15-year-old sisters were found five days later, floating in a river.

In both Spotsylvania cases, there were no witnesses and almost no evidence left behind. The only clues were a few tiny fibers and a couple of strands of hair.

Special Agent Doug Deedrick, an FBI trace evidence expert who was the lead forensic agent in the case, had a hunch all three slayings were linked. But the question was whether he could prove it.

One of the clues was some pink fibers found on Kati Lisk's body.

"I said, 'Pink fibers, I think they look like a bath rug of some type.' Everyone was looking for this pink bath rug for me," Deedrick said. "With Sofia, for instance, I had some dark blue acrylic fibers that I was looking for because I found the same types on Kati and Kristin. And when I turned Sofia's shirt inside out, I actually pulled off eight or nine blue fibers."

Serial Killer on the Loose

There was no doubt: There was a serial killer loose in Spotsylvania.

A task force consisting of the FBI, Spotsylvania County and state police chased more than 12,000 leads. Investigators compared evidence against items from more than 45,000 unsolved cases and checked DNA samples against 1.2 million genetic profiles. The FBI performed more than 10,000 examinations on the three hairs and 190 fibers recovered from the bodies.

But it would take authorities five years to find the killer.

The break came in June 2002, when a 15-year-old girl watering flowers in her front yard was abducted at gunpoint, in broad daylight, in Columbia, S.C. The kidnapper forced her to climb into a container, which he put into the trunk of a car.

He drove her to an apartment, where he handcuffed the girl and repeatedly raped her over 18 hours.

But while her captor was asleep, the girl managed to escape and lead police back to the apartment. The suspect, identified as 38-year-old Richard Marc Evonitz, was gone.

Police caught up to Evonitz two days later, on June 27, in Sarasota, Fla., where he was trapped after a brief, high-speed police chase. He shot himself in the head, leaving investigators to wonder: Was he the Spotsylvania serial killer?

News Clippings and Small Fingerprints

Police learned Evonitz had once lived in Spotsylvania. In his apartment, they found a 1997 newspaper clipping about the abduction of the Lisk sisters.

Deedrick, a 30-year veteran of the FBI, knew he had to go to South Carolina.

"In searching the apartment, I was keying in on items that might have been blue, dark blue, red," he said. Investigators dusted for fingerprints inside the trunk of one of Evonitz's cars.

"And I saw four fingerprints, it looked like four fingers, small," Deedrick said. "And they were in a position that indicated that probably somebody had been in the trunk."

Deedrick raced back to the FBI lab to examine the 600 pieces of evidence.

There were some forensic matches. The pink bath rug that Deedrick had been looking for for five years ago was among the discoveries. Police found it in the bottom of a box in Evonitz's linen closet.

Furry Handcuffs Provide Clue

"I [took] the fibers off and looked at them under a microscope - [they were] the same fibers that I found on Kati," Deedrick said.

Another key clue was the pair of handcuffs the South Carolina girl had been wearing when she escaped.

"Handcuffs by themselves didn't strike an interest to me, until you open the bag and you realize that they're furry handcuffs and there's fibers on them," Deedrick said. "And it looked black, but when you hold it up to the light, you can see that there's a real dark blue coloration to them."

The same dark blue as the fibers found on all three Virginia girls.

'The Right Stuff'

Finally, there were the fingerprints found on the trunk lid. They matched those of Kristin Lisk.

"Fingerprints were really the icing on the cake in this," Deedrick said.

Evonitz's DNA matched that of a head hair found in Kati Lisk's sock and two other hairs found on the two other slain girls.

In mid-August, police and the FBI announced that the Silva and Lisk murders had been solved. They were able to tell the families of the Spotsylvania victims that they now knew for sure that Evonitz was the killer.

"Early on, when I was talking with Patti Lisk, the mother of Kristin and Kati, I told her that when I get the right person, I'll know," Deedrick recalled. "And she reminded me of that some time later. And when I got the right stuff, I knew."

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Tiny Fibers Helped FBI Nab Serial Killer

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May 21, 2003 -- On the day she was abducted, 16-year-old Sofia Silva was sitting on her front porch in Spotsylvania, Va., doing homework. It was Sept. 9, 1996. Five weeks later, investigators found her body in a nearby creek. Eight months later, it happened again, in the same town, just 70 miles south of Washington, D.C.