HOW SHOULD CRIME be punished? For many crimes, my wife’s answer is torture. In her view it has all the virtues to be sought in a punishment: it would be an effective deterrent, proportionate (because similar) to the crime, and cheap. This is an unpopular view, at least in our social circles. The dinner parties are usually saved only by the refusal of other guests to believe she means it.

My wife is not concerned with seeming nice, or much with being nice.

But most modern Brits are, and few more so than the New Conservatives. For the nice, punishing crime is a tricky business because all punishments are, by necessity, nasty. Torture is very nasty, of course, but imprisonment is quite nasty too. So it was not surprising to learn that Tory thinking is turning against prisons. Mary Ann Sieghart wrote on the comment pages last week that Edward Garnier, the Shadow Minister for Home Affairs, thinks imprisoning criminals “is hugely expensive and not working”.

This anti-prison position is certainly fashionable. But is it also true? Mr Garnier claims that prisons are failing because recidivism rates are high. Seventy per cent of prisoners are convicted of another crime within two years of being released from prison.

This is a peculiar objection to imprisonment — rather like complaining that your TV isn’t working because it does not defrost chickens. Reducing reoffending is not the purpose of prison. Its purpose is to reduce offending. It does this by deterring people from committing crimes and by positively preventing them from doing so while they are inside.

But doesn’t the high recidivism rate show that prison is not an effective deterrent after all? It does not. Testing the deterrence value of prison by observing the portion of ex-prisoners who commit crimes is ludicrous. It is a bad case of the statistical error of “sample bias”. Prisoners are, by hypothesis, people for whom the threat of prison is an insufficient deterrent to crime. That prison does not deter those who end up as prisoners tells us nothing about how much it deters the rest of the population, nor therefore by how much it reduces crime.

Effective deterrents are consistent with a high recidivism rate. Imagine a punishment so dreadful that only the most desperate psychopath would risk it by committing a crime. No better deterrent could be devised. Yet it may lead to 100 per cent recidivism. After his punishment the desperate psychopath is still a desperate psychopath.

Indeed, he will probably be more desperate. Once convicted of a crime, it becomes harder to “go straight”, if only because employers are reluctant to hire people with criminal records. Being convicted of a crime can increase the chance of committing further crimes and suffering further convictions. This well-known fact helps to deter many from committing crimes in the first place. Far from being counter-evidence to the deterrence value of prison, recidivism is part of the deterrence mechanism.

Recidivism is a red herring. Nevertheless, Mr Garnier may be right that prison is too expensive a way of reducing crime. Alas, Mr Garnier offers no argument beyond pointing to the cost to taxpayers: £37,000 per prisoner per year. He seems to think that upon hearing this figure we will all leap to the conclusion that prison is too expensive. But it would be a leap of faith, because you cannot tell from its price alone whether or not something is good value. Is £15,000 good value for a car? It depends, of course, on what the car is worth. The same goes for prison. If keeping someone in prison for a year is worth more than £37,000 then it is money well spent.

So, is it worth more than £37,000? Imagine a town of 500 adults that has nabbed its local criminal. They convene a town meeting to decide whether to spend the £75 each required to send him to prison for a year. What do you guess they would decide? It would depend on the kind of crimes he commits, of course. But if he were a typical British criminal — if he would willingly smash a pint glass in your face, kick your head in and break into your house at night — then I am sure most people would consider £75 a bargain.

When imprisoning criminals is such good value, we should be doing much more of it. Especially when, contrary to popular belief, Britain has such a low rate of imprisonment. Admittedly Britain imprisons a higher percentage of its population than any other Western European country. But this is a misleading measure, since it takes no account of the portion of the population who commit crimes. Allow for the extraordinary criminality of the British, and Britain has a low imprisonment rate. Whereas Britain imprisons 12 people per 1,000 crimes, Spain imprisons 48 and Ireland 33.

Measured properly, high imprisonment rates correlate with low crime rates: Spain and Ireland, for example, have lower crime rates than Britain. And when Britain began increasing its prison population 13 years ago, the number of crimes began falling. In 1993 the prison population was 49,000 and the number of recorded offences was 19 million. By 2005 the prison population was 75,000 and the number of crimes 11 million. The same story can be told for the US, where the crime rate has fallen steadily as the prison population has climbed.

Someone who knows these facts, as Mr Garnier must, may still favour reducing the percentage of criminals sent to prison. But it cannot really be because he thinks prison doesn’t work. It can only be because he is very, very nice.

Jamie Whyte is a philosopher and author of Bad Thoughts: A Guide to Clear Thinking

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