The revolving door of Irish prisons is spinning again. Today we reveal that the system is full, with hundreds of offenders being temporarily released, some having served only half their sentences. There are currently 3,681 prisoners in custody, compared with 3,345 last year. This represents an increase of 65% on the 2,230 inmates incarcerated in December 2006. There are 361 offenders on temporary release, an increase of 172 on last year. The prison service has confirmed that it is operating “at, near or slightly in excess” of capacity.

As a result, prison governors are effectively operating a revolving-door system, with criminals convicted for robbery, theft, drug possession and public-order offences being freed prematurely. This is unacceptable. Releasing prisoners prematurely undermines the entire criminal justice system. It suggests to would-be criminals they may get off lightly, blunting the deterrence prison is supposed to provide.

The prison service is already struggling to cope with drugs, smuggling and attempts by some inmates to run crime empires from their cells. Full-to-capacity conditions mean they must now cope with overcrowding and will be less able to provide willing inmates with reform opportunities.

The government’s response to all this is to build new jails. Thornton Hall in north Dublin is intended to house 1,400 inmates in individual cells, and will have the capacity to cope with 2,200. If it eventually gets built, it should ease the overcrowding problem, but for how long? There is an upward trend in incarceration — with more gardai prosecuting more criminals, fewer suspects getting bail and judges handing down stiffer sentences.

It is past time for a more imaginative approach to dealing with petty criminals, who are clogging up prison spaces unnecessarily. Eurostat says the number of people in Irish prisons has grown 4% per annum over the past 12 years. This puts Ireland in joint-fourth place on the league table of growing prison populations.

The evidence suggest that prisons, while staffed by well-meaning professionals, are not rehabilitating inmates. There is a serious underlying issue involving the mental health of inmates. According to research from the Central Mental hospital, published last July, Irish prisons are being used as “psychiatric waiting rooms”. It found 60% of all female inmates and 35% of male prisoners had a history of mental illness. Some prisoners should be in treatment, not in jail.

The Irish Penal Reform Trust rightly points out that sending fine-defaulters to prison makes little sense, even in repeat circumstances, as they pose no risk to society. What is needed is a well-resourced and workable system of community sentencing. A government-commissioned report concluded earlier this year that the current provision of community sanctions is “embarrassing”, outdated and in need of overhaul. Sean Lowry, its author, said judges are referring too many low-risk offenders to the probation service, putting it under strain and preventing staff from dealing with higher-risk criminals. The number of hours of community service imposed for all crime types is high, resulting in poor completion rates.

The prison system needs to deal with serious criminals and prevent them operating empires from behind bars; it must reduce drug use and provide an environment in which rehabilitation is possible. Revolving-door prisons in which the authorities act as busy hotel receptionists mean none of this can happen.

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