Also supporting other candidates means that they won’t loose their deposit (the money they put down to appear on the ballot paper, which they will loose if they don’t receive enough votes) and can continue to fight elections in your area.

Furthermore, the electoral system will never change to benefit third parties if only voters for the main parties turn out to vote, if you want to see a change then you must show that there is demand for other parties to be represented.

Parties are also awarded ‘Short Money‘ (funding) depending on the number of overall votes they receive.

By voting you can select the person you want to represent you and help them keep their job, or by voting for other candidates you can help remove an incumbent.

Blank Votes and Spoiled Ballots are read out at the count, along with the results and are also included in subsequent reports. Your apathy towards the political parties will be heard not just forgotten.

Low election turn-outs result in a government that does not truly have the democratic mandate of the population. Compulsory voting would ensure the governing party has the majority of the country on its side, and better reflect the wishes of the people.

If an individual is forced to vote they would/should make an effort to become more informed on the issues that the various parties are campaigning about, and the issues that affect themselves and their local electorate. 

Forcing people to vote (against their will, in the case of some Jehovah's Witnesses) does not ensure a greater democratic mandate. There will be voters who are voting not because they want a particular party to win but simply because they have to vote.

Bullying tactics should never be used in free and fair elections because they undermine the democratic process, and compulsory voting works only when backed up with fiscal punishment for those who don't vote.

Democracy loses out when people get turned off politics and don't get involved. There is currently no reason for apathetic, non-voting members of the public to be interested in politics.

If forced to appear at the polls, even to register an abstention vote, the population of the UK would become more involved in the political process, ensuring that parties have to listen to what the people are saying.

People only become apathetic because the politics of the main parties are not relevant to them. Getting rid of apathy does not require reforming the electoral process but making sure the politics of the day engage the public. Compulsory voting would merely be addressing a symptom of a wider problem, not the root cause.

Australia and other countries already have compulsory voting in a modern, western liberal democracy, so it is not an idealistic aim to make it compulsory in the UK.

Just because it 'works' in other countries does not mean that it should be implemented here. 

Further questions are raised about how people will vote when they remain apathetic to the process but are compelled to vote: it can hardly be said to 'work' when some people may vote for a candidate at random because they are still uninformed and ignorant of policies. 

We already hold various functions important to the running of the country as duties in this country, such as the payment of various taxes.

Voting is arguably the most important civic function because it ensures our democracy continues; there would be enormous outcry if a government were elected by a small turn-out, which is the way the trend is heading.

We also cannot be seen to be exporting democratic values around the world (e.g. the Middle East) when not enforcing those values at home. It would be hypocritical to say that voting in your leaders is important abroad, while not caring domestically.

Voting is not a duty but a right, and as with all rights, people must retain the ability not to exercise it. A 40% abstention vote would be more embarrassing to the winning party than a 60% turnout, because it highlights further the dissatisfaction of the public with the politics of the day.

Paying taxes is a duty because everyone uses the services the government provides, such as roads, schools, hospitals and so on, regardless of whether they vote or not, and regardless of which party they voted for.

It is not hypocrisy because we still offer the democratic process, holding free and fair general elections no later than every 5 years. Hypocrisy would be to export democracy while eroding it at home, removing the right to vote and so on. This is simply not the case.

In todays times a vast majority of people don't really care about what's happening in politics, or simply don't care enough to vote thinking that their one vote won't change anything. If there was compulsory voting I believe that more people would take an interest in politics and make their vote count for something.

Instead of trying to engage people by force, how about introducing political education in schools and encouraging political conversation. How about educating the public on how Westminster affects them? People vote with their feet. If they are not interested, they are not interested! The government should be trying to engage people by other means, not compulsory voting. It may improve low turnout but will not affect what people actually think about politics.

If the purpose is to increase turnout, weekend voting would be the more sensible option. It gives people more free time in which to vote, and doesn't have the problems that coercion brings with it. It doesn't address the wider problem of apathy, but treats the non-voting problem more acceptably than compulsory voting does.
 Better yet, introduce a public holiday on election days and provide free public transport to and from polling stations.

Simply changing the day elections are held doesn't make it any more attractive for people to vote. Those people who don't care won't care any more now that an election is on a Saturday, regardless of how much easier it is for them. Just as people have better things (in their opinion) to do during the week, they will have alternative activities for the weekend.

Compulsory voting addresses the fact that people simply don't turn up to vote, which weekend voting doesn't.

Voting holds a special place in a democracy; it is the very foundation of the mandate our elected representatives hold. To turn it into something everyone over the age of 18 must do would take away something from that.

A non-vote (i.e. staying at home) sends a more powerful signal of apathy than does a spoilt ballot or abstention vote; a non-vote says that the citizen is dissatisfied with the entire process, that politics do not address any concern she has. A spoilt ballot or abstention vote in a compulsory election, however, merely expresses dissatisfaction with the particular candidates in the constituency, and hides the deeper malaise that may be there.

Compulsory voting merely sweeps under the carpet the legitimate dissatisfaction many people feel with politics, and will not lead to the regeneration of politics that its proponents suggest. Many people will merely vote at random, because 'they have to', rather than expressing their apathy.

A person who conciously elects, in their own mind, that they do not wish to participate in an election process, for whatever reason(s) they may have, should not be legally obliged to vote or in any way participate if they choose not to do so.

Better to register dissatisfaction with politics by actively registering a non-vote. Ballot papers could include an abstention box to properly register this message.

Spoiling a ballot in order to show that one feels no candidate is suitable, or even that they are dissatisfied with the entire system, sends a message out much more clearly. If one simply did not attend the vote at all this could be for many reason - sickness, forgetfulness, pure laziness - and is not making any kind of political statement.

Forcing people into voting when they are disengaged from the politic process will exacerbate this problem; no one likes doing something simply because they have to. Election results may be skewed, particularly in marginal seats, by voters who vote at random because they still don't bother to find out about the candidates, parties and policies involved.

Rather than forcing people to vote, more should be done to engage the public in political life. Westminster is a distant body, detached from real life, and should be made more relevant and more deserving of the public's trust, for example by releasing full details of MPs' expenses. 

Citizenship classes should teach the importance of the electoral process, and the history of the suffragette movement, the reform bills of the 19th century and the responsibilities of living in a democracy.

As noted elsewhere, forced attendance would lead to increased political awareness, and an abstention option would offer a 'none of the above'/'I don't mind or care' choice instead of forcing people to choose a candidate randomly.

Because the number of voters would increase, politicians would have to be active in engaging with the public and therefore become "more deserving of the public's trust" as you suggest.

Citizenship classes are irrelevant here; having them doesn't negate the need for compulsory voting. 

Only where the ballot offers a "none of the above" option can compulsory voting being truly democratic. However, where this is the case if the "none of the above" option achieves over 50% of the vote does democracy simply fail and the state fall into anarchy? that would be truly democratic, although, hardly pragmatic. Consider that in most British elections the majority is not in fact the winning party, but in fact, the non-voters.

It is highly unlikely that this would be the case across all 600+ constituencies of the UK.

Furthermore, an abstention vote means 'do not count me', not 'don't elect anyone'. The number of votes in this category therefore do not matter, so long as the real candidate with the most wins the seat. (It would be different if the option were to Re-Open Nominations, but that has not been proposed.)

Would you force someone to vote even if they were actively uninterested in politics? Even if they were determined to cross a random box? Even if they did not even know the political party in power/opposition?

If you force everyone to vote you make it a criminal offence to be incredibly apathetic, so the incredibly apathetic people will merely vote insensibly, counting against the people who are actually voting on the basis of informed opinion. In an extreme case, idiots could sway the result of an election.

If your not even bothered enough about the future of your country's government to even turn up at the polling booth at each general election, then you don't get a say, and I think thats actually good. Forcing uninterested people to vote is not really democratic its just random.

You might want to decide who's in power by throwing the dice instead.

Knowing that turnout would be substantially increased would lead to far more active campaigning by all political parties. This in general would raise political awareness and negate the problem proposed. 

Furthermore, an option to 'abstain' on the ballot paper would accommodate anyone who truly does not wish to have a say in the running of their country.

There really is no point voting a lot of the time anyways because they always promise to do this promise to do that but then once they are in office they do what ever the hell they want anyways. It is always promises that are broken you can't trust politicians they are all bred to lie and miss lead in the end.

In a compulsory voting system promises are far less likely to broken as everyone will attend at the ballot box, far increasing the chance that the country would rebel against an incumbent government. This therefore forces politicians to be more careful and more attentive to the public mood.

Punishing someone for not voting would add insult to injury. By not voting, a person has actually made a huge sacrifice – they have waived their right to have any say in the running of their country and possibly incurred extreme consequences if the person who is voted in decides to persecute them. If a person doesn't vote, knowing the full consequences of their actions, it is akin to surrendering in battle – an action that, rather than 'lazy', is a powerful decision in itself, not something you do without a good reason.

On the contrary when a person votes, they are making use of their right. They are reaping a reward – it is like one free voucher to slightly more political power than they would otherwise have. While I am not saying it is an unvirtuous thing to vote – I admire anyone who votes for a genuinely ethical party against the advice of a strong majority – I do not think rewarding a reward makes a lot of sense.