New prison may be needed to handle overcrowding, Minister for Justice says

There are 4,400 spaces in the system but the need to separate gangs means the true capacity is about 4,200

The Government may construct a new prison to deal with overcrowding in addition to expanding existing prisons, the Minister for Justice Simon Harris has said.

One possible location for a new facility is Thornton Hall in north Dublin, the Minister said. The site was purchased by the State in the mid-2000s as a location for a new super-prison to replace Mountjoy, but the plans were later shelved during the recession.

This week, Mr Harris announced the expansion of Castlerea, Cloverhill, Midlands and Mountjoy prisons, which will add up to 400 new cells to the system over the next five years.

Speaking at the annual conference of the Prison Officers Association (POA) in Galway on Thursday, he said an entirely new prison may also be required due to the ever-growing prison population. “The era of not expanding prison spaces is over,” he said.


Mr Harris said he is “very conscious” that the Department of Justice owns Thornton Hall and that “we have to prepare for very significant capital expansion”.

As of Wednesday, there were 164 prisoners without beds and the prison system was operating at 104 per cent capacity. In the last year, prison numbers have increased by 23 per cent.

Mr Harris said more prison spaces are needed because of population growth, the appointment of additional gardaí and judges and new legislation mandating longer sentences for certain crimes.

“We must prepare for a period of significant population growth and ensure we have the capacity to meet the needs of the criminal justice system.”

Director general Caron McCaffrey confirmed in the short term bunk beds are being ordered for Mountjoy Prison to reduce the numbers sleeping on mattresses. However, many cells are too small for bunk beds as they are designed for single occupancy, she said.

The need to separate some prisoners from rival gangs is also placing pressure on the system. In theory, there are 4,400 spaces in the system but the need to separate gangs means the true capacity is about 4,200, Ms McCaffrey said.

Overcrowding is causing an increase in assaults on both prisoners and staff, the conference heard. Between 2021 and 2022 there was a 46 per cent increase in assaults on prison officers, from 91 incidents to 134.

“Some of these assaults have been extremely serious and will have a lasting impact on those who were injured and their families,” POA General Secretary Karl Dalton said.

Injuries to staff have increased by 63 per cent during the same period. At the same time, prisoner on prisoner assaults increased by 52 per cent to 380.

“These statistics speak for themselves, and unless the overcrowding and recruitment issues are resolved these levels of violence will increase in all areas – and inevitably lead serious injury and further fatalities,” Mr Dalton said.

Conor Gallagher

Conor Gallagher

Conor Gallagher is Crime and Security Correspondent of The Irish Times