How should we treat convicted criminals? This is a matter of continuing public debate, and varies enormously across countries. Even within the so-called developed world, there are wide variations. The US, for example, imprisons more people per capita (over 700 per 100,000) than any other country in the world. At the other end of the spectrum are the Scandinavians. Norway, for example, has one of the lowest, at 66 per 100,000.

While the composition and severity of crime varies, the US and the Scandinavian model represent different philosophies. The US system focuses more on punishment, whereas the Scandinavian model emphasises rehabilitation: treatment and support aimed to help the offender become a law abiding member of society. This might include developing skills to improve employability or treating mental health problems, for example.

The UK falls somewhere in between these two models. Although it has the highest prison population per capita in western Europe, the country has experimented with initiatives aimed at diverting low level offenders away from prison.

One of the largest such schemes – Operation Checkpoint – is being run by Durham Constabulary. This “deferred prosecution scheme” allows offenders for certain types of relatively low harm offences (such as theft or criminal damage) to avoid prosecution if they participate in a programme that addresses their causes of offending – such as mental health issues or substance abuse. The first set of results from this programme, recently published, show a 15% reduction in reoffending rates when compared to similar offenders who did not participate.

A back of the envelope cost/benefit analysis suggests that the programme also represents good value for money, with the benefit to society from reduced re-offending estimated at £2 million against a cost of half a million for running the programme. Of course, while not every rehabilitation programme in the UK has been rigorously evaluated, these results are consistent with other evidence across England and Wales indicating that non-custodial alternatives can reduce crime.

Retribution or rehabilitation?

The effective response to crime has always been a matter of debate. While the retributive idea of justice seeks to inflict a cost or hardship on the criminal as a just response to crime, the rehabilitation model seeks to provide support that can reform the criminal.

While this debate has often been cast as one between those who fully believe in punishment and those who want to see prison time completely cut and replaced with rehabilitative programmes, most people believe in both. The debate is more often about what the right mix is.

In the UK, for example, there is wide public support for tough criminal justice sanctions. But there is just as much support for rehabilitation. And when presented with evidence around the cost of prison (roughly £40,000 per prison place per year), a majority support looking into cheaper alternatives to prison: meaning there is public support for alternatives to custody that can rehabilitate criminals.

A particular type of alternative to custody is a deferred prosecution agreement, where criminal charges are not brought against defendants if they fulfil certain conditions. The success of Operation Checkpoint will no doubt spur more interest in the area.

Reoffending rates

An international comparison reveals some interesting trends. Norway moved its focus from punishment to rehabilitation (including for those who were imprisoned) 20 years ago. This was followed by large reductions in reoffending rates. Compared to a reoffending rate of around 50% within a year in the UK, Norway’s is around 25% in five years.

There is much to learn from this. A lot of people processed within the criminal justice system have vulnerabilities that can make them prone to offending, which might suggest why rehabilitation can be so successful. Recent evidence suggests that the UK prison population has serious levels of self-harm. And a recent report finds that 90% of the UK’s prison population suffer from metal health problems. Releasing such people without investing in their treatment is bound to lead to reoffending.

Though less dramatic, the same report finds that nearly 40% of people detained by the police also suffer from mental health issues. A substantial portion of criminals, then, could benefit from support rather than punishment. Locking up or otherwise criminalising people with these vulnerabilities also raise ethical issues. In particular, what would be a just response to crime committed by the vulnerable?

The economics of crime

From an economic perspective, rehabilitation makes sense. A recent study that colleagues and I undertook across England and Wales provides illustrative examples of changes in sending more people to prison (a proxy for a model that emphasises punishment) versus community sentences (a proxy for a more rehabilitative approach). Based on a statistical model using data on case disposals and crime rates across England and Wales, it provides estimates of how changes in case disposals affect crime rates.

For example, sentencing 1% more offenders to prison for property offences (including theft and handling) is estimated to reduce next year’s recorded crimes by 2,693. But a similar 1% increase in community sentences reduces these offences by 3,590. When one considers that community sentences cost on average a quarter of prison sentences, it appears there is scope to reduce property crime (approximately 72% of recorded crimes in the analysis) more cost-effectively and humanely through a greater use of community sentences instead of prison.

The results suggest that initiatives like the Durham model could be used more widely, leading to a more cost effective and humane criminal justice system.

Views on crime and punishment differ. Yet almost everyone would agree that we care about crime because of the harm caused by it. One does not have to have any particular ideological bent to advocate an approach that reduces harm. There is evidence that rehabilitation (including within prison) reduces crime and can be cost effective. Economic analysis therefore, reinforces the idea that punishment is not the best solution for reducing the harmful impact of crime.