Prisoners who are allowed temporary release for vocational or family-related purposes such as Christmas leave are less likely to reoffend than those who are not, according to Government-funded research on recidivism rates among prisoners.
The study, conducted by a research team led by Prof Ian O'Donnell of UCD's Institute of Criminology and funded by the Irish Research Council for the Humanities and Social Studies, builds on the findings of research published by the institute last year.
This found that more than a quarter of the State's prisoners are back in jail within a year of their release, while almost a half are serving new sentences within four years.
The researchers examined a total of 19,955 releases from Irish prisons between January 2001 and the end of November 2004.
About one in four of those studied had been granted some form of temporary release during their time in prison, with most of these allowed to spend one or more days with family members. Others were permitted to look for work or to participate in vocational activities.
The researchers then charted the level of reoffending by this group of prisoners over a four-year period. They found that offenders who were allowed family leave were 5 per cent less likely to reoffend by the end of this fourth year, while those who were granted vocational leave were 4 per cent less likely to reoffend.
According to the researchers, this "modest but meaningful" trend is evident regardless of the age of the offender, the type of offence which they have committed and their previous experience of incarceration.
They note that the average cost of keeping each prisoner in jail in Ireland in 2005 was €90,900.
As a result, they say the findings could be used to "offset any perception of lenience with the finding that these individuals are less likely to end up back in prison, at considerable cost to themselves and their families, to say nothing of the financial burden placed on the taxpayer."
"What we are saying I suppose is that at one level, the prison service is accurately identifying the good risks, but that also if the system trusts prisoners that it will be rewarded through better behaviour in the long run," Prof O'Donnell told The Irish Times.
"If an intervention to deal with obesity or cancer mortality etc could be shown to have a statistically significant effect, this is something that would be taken seriously by policy-makers."
Earlier this week, Minister for Justice Brian Lenihan announced that more than 100 fewer prisoners had been granted temporary release over the Christmas period this year than were granted this release last year.
Revealing that 137 prisoners were allowed varying periods of temporary release this Christmas, Mr Lenihan said this figure represented approximately 4 per cent of the prison population and was a "significant reduction" on the 238 prisoners released last year.
Last week the Irish Prison Service also confirmed that seven male prisoners who were granted temporary Christmas release over the past five years remained unlawfully at large.
Prof O'Donnell noted that there was always a risk that an individual would not return from temporary release, but this is not the same as saying that there was a risk to the public from their failure to return, as individuals who qualified for release were preselected and were judged not to pose a risk to the public.
He added that the number who had failed to return was a very small percentage of the total number of individuals released during that period, and that a temporary release programme could not be "risk-averse".