The biological approach can be considered as high in validity. Most research is conducted using scientific and controlled methods such as brain scans, which have a standardised procedure to follow. A strength of the biological approach is that it provides clear predictions, for example, Raine et al found that murderers had lower glucose metabolism in one side of the brain than the other. He found this using brain scans on them to see their brain activity, which was an objective method. This reduces the risk of them showing demand characteristics to appear better, but also researcher bias. Therefore the approach is more likely to have valid supporting research.

Due to the standardised procedure of brain scans, they can be said to have high reliability. PET scans use a radioactive marker as a way of studying the brain at work. What the scan therefore enables researchers to do is to provide ongoing pictures of the brain as it engages in a mental activity. This means they have a set procedure to follow, and by being conducted in a lab they are controlled and scientific. Therefore, this makes them easy to replicate to test for consistency with findings. 

- Another implication of using a deterministic explanation is that society may see some treatments/ rehabilitations as pointless, such as token economies/ anger management, therefore withdraw any help with the view it’s a biological problem

- One application could be that it may provide improvements to current treatments as it may suggest using biological treatments along side treatments such as anger management.
- Many researchers have concerns using brain imaging in the legal system to determine criminal responsibility. Imaging cannot tell what a person was thinking at the time of the violent act but can show deficits in areas linked to aggression and impaired volition, which would suggestion reduced culpability (blame-worthiness). 

Hippocampus

Hypothalamus