More than a third of prisoners are being released early before they have served their sentences or because they have qualified for time off for good behaviour, according to new figures from the Department of Justice.
There were 3,065 early releases from prisons last year from about 8,200 committals.
The revelation comes less than a week after the visiting committee of Cork prison said overcrowding was so bad that prisoners were being released early to make way for new committals.
The latest figures were obtained by Fine Gael's spokesman on justice, Jim O'Keeffe TD.
He dismissed claims by the Tánaiste and Minister for Justice, Michael McDowell, that the releases were "temporary releases" granted as part of sentence management and prisoner reintegration.
"I don't accept that because it doesn't stand up to scrutiny," Mr O'Keeffe said.
"When I got figures last week relating to 470 early releases in Cork prison last year, the Tánaiste said it was all about sentence management.
"Then a few days later the prison visiting committee came out and said the early releases were happening because of overcrowding and to make way for new committals. And now I have got figures for the whole country, and I find that it's the same everywhere."
He said the early releases were being forced because the prison system was overcrowded following the closure of a number of facilities to cut costs.
The problem was exacerbated by the fact that 2,000 fine defaulters were jailed annually because the Government had failed to formulate alternative penalties.
The new data shows that most early-release inmates are being set free from the State's most crowded prisons, including Mountjoy, Cork and Limerick, where 652, 470 and 375 prisoners respectively were released early last year.
However, the figures suggest the small open prisons of Loughan House, Co Cavan, and Shelton Abbey, Co Wicklow, are apparently being used as clearing houses to which inmates are being transferred before being released early.
At Shelton Abbey, which has an operational capacity of 56, 239 prisoners were released early last year. At Loughan House, which has an operational capacity of 85, 314 inmates were released early last year.
The figures were contained in a reply by Mr McDowell to a Dáil question by Mr O'Keeffe.
In the reply, Mr McDowell pointed out that temporary release rates on any given day were running at about 4.5 per cent of the prison population. This figure was about 20 per cent just over 10 years ago.
He describes as "temporary releases" the 3,065 early releases last year. He said 70 per cent of the released prisoners were in the last month of their sentence, with 31 per cent in the last week.
He continued: "The generally- accepted view is that the risk to the community would be reduced by planned reintegration of offenders compared with their return to the community on the completion of their full sentence.
"Each case is examined on its own merits and . . . the safety of the public is paramount when decisions are made on temporary release applications."
He said prisoners were considered for "temporary" release in various circumstances, including for employment or training programmes, on compassionate release, because of ill health, family-related circumstances or for reintegration purposes.
