Murderers and other long-term prisoners are spending an average of 17½ years behind bars before being release, according to the Parole Board of Ireland's annual report.
Last year, almost 100 recommendations were made to the Minister for Justice by members of the board.
In Ireland, murder carries a mandatory sentence of life imprisonment. Other serious offences such as manslaughter and rape can also lead to a life sentence.
However, cases are usually reviewed after seven years.
The Minister for Justice has the final say, but will always consider the advice and recommendations of the Parole Board of Ireland.
Speaking at the launch of the board's annual report today, Minister Frances Fitzgerald said "lifers" are spending longer behind bars in recent years.
"Over the last 30 years, [sentences have] gone from an average of 7½ years for people who have committed murder, right up to 17½ years now," she said.
Minister Fitzgerald also said that an important consideration for the Parole Board is the involvement of victims in the review process.
"The issue of victim representation on the Parole Board is one which I intend to explore in the context of bringing proposals to Government on strengthening the position and role of the Parole Board," she said.
Chairman of the Parole Board John Costello, said the results post-release are encouraging:
"When prisoners are moved back into the community, with proper supports, they can become well-functioning members of society," he said.
"And that is of benefit to everyone."
Those granted parole are monitored and can be called back into prison at any time.
According to members of the board, public safety is of the utmost importance when a vase is reviewed.