This article is part of the Beyond Prison series, which examines better ways to reduce re-offending, following the recent State of Imprisonment series.

Is the purpose of incarceration to punish wrongdoing, or to protect society from dangerous individuals? Is it to make an example of criminals to deter others, or to reform those who stray beyond the bounds of acceptable behaviour? There are arguments for each of these approaches to incarceration, and they often stand in conflict with one another.

Currently, sentencing policy in Australia reflects an apparently arbitrary mixture of all four approaches. The result is that incarceration is often ineffective and even counter-productive.

Until we decide what prisons are for, we cannot formulate coherent public policy that prevents the arbitrary or unfair use of incarceration against vulnerable people. Australia’s use of incarceration is often determined by inscrutable factors beyond the apparent threat that individuals pose to others.

The expected benefits of incarcerating young Indigenous men from remote communities for unpaid driving fines is unclear. So is the purpose of incarcerating people for non-violent crimes related to drug dependence. But the financial and personal costs are massive.

Prison is failing as a deterrent

Evidence clearly shows that incarceration does not act as a strong deterrent, since most people – particularly young people – do not make rational, cost-benefit analyses before engaging in illegal behaviour. Recidivism rates in Australia and the US clearly indicate that prisons are not “rehabilitating” most offenders.

Prisons do keep people off the streets while they are incarcerated, but the average sentence is quite short, so the incapacitation effect is limited. We also know that many people resume illegal and risky behaviour shortly after they return home.

Recently released prisoners experience extremely high rates of fatal drug overdoses and other unnatural deaths during their first few weeks in the community. Far from “rehabilitating” them, by reducing their tolerance to opiates without effectively treating their drug dependence, incarceration puts the lives of drug-dependent prisoners at risk.

This clear harm to prisoners should be outweighed by a benefit to broader society. But in the case of people incarcerated for non-violent drug-related crimes, the net benefit seems unclear.

Punishment alone is poor policy

Do we gain anything simply from seeing punishment inflicted on those who have behaved unacceptably? It seems obvious from the public reaction to high-profile violent crimes that some have a strong desire to see retribution visited on those who harm others.

In handing down a severe sentence, a judge, on behalf of society, condemns the behaviour of the offender. The length of the sentence is taken by many people to indicate the level of condemnation. As such, elements of the public and the media often decry “short” sentences for violent crimes as an indication that the legal system does not take these crimes seriously.

However, beyond a desire for retribution, what is there to recommend a long sentence over a short one? A 25-year-old man who is incarcerated until he is 30 has experienced a catastrophic blow. Beyond the loss of his liberty, his relationships with his friends and loved ones are likely to change dramatically and may be destroyed altogether. His chances of finding stable housing and fulfilling work after he is released are poor.

The characterisation of short sentences as somehow trivial dramatically underestimates the profound impact that even brief periods of incarceration can have on people’s lives. Incarceration is an intrinsically harsh punishment. Why then do we mete it out so readily?

Time to reform practices with medieval origins

Punitive practices in English-speaking countries have their roots in the medieval period. Initially, incarceration was not a punishment in itself but simply a way of detaining people until corporal punishment was delivered.

This strongly retributive approach to criminal sanctions came about at a time when its impact on crime could not be measured. It was believed that harsh punishments were inherently just and that delivering them in public would have a strong deterrent effect. The torturous methods of execution for which the medieval period is known serve as a vivid reminder of the barbarity of that system.

The tide turned on this approach in the 18th century. Sentences of corporal punishment began to be commuted to forced labour, sometimes combined with transportation to Australia. This was the birth of incarceration as we now know it, as a punishment in itself.

Since then, the focus has shifted to rehabilitation. However, a strong punitive element remains in our current system.

English-style law is subject to a constant process of ad-hoc additions and subtractions, but this process is not guided by a coherent underlying philosophy. After centuries of revision and augmentation, far from a consistent system with a clear rationale for when, how, why and against whom incarceration should be used, we have been left with a monster designed by committee.

There are clearly people who present so great a danger to others that something must be done. The public rightly expects to be protected from those who have committed acts of terrible violence and who demonstrate no remorse or desire to change. It may very well be that prison is the only place for such people.

However, such people do not comprise the majority of the prison population. We use incarceration against many people who do not pose any serious threat to others. We also have no reason to believe that people with drug-dependence problems or those who cannot afford to pay fines will be “reformed” by spending time in prison.

It seems unlikely that the retention of punitive elements in a system that ostensibly seeks to rehabilitate and reform is improving outcomes. Centuries after corporal punishment was phased out in the West and the modern prison was born, we are yet to seriously confront this persistent, base element of our approach to criminal justice.

If the punitive approach to incarceration is harming a great many people without making the rest of us safer, perhaps it’s time we left it behind.

You can read other articles in the Beyond Prison series here.