Closure of main prison housing sex offenders should be a priority

Group established to advise the Government on future prison capacity needs has called for the decommissioning of the prison at Arbour Hill in Dublin

The prison at Arbour Hill in Dublin currently houses around 135 long-term prisoners. File picture: Billy Higgins

The closure of the country’s main prison for housing sex offenders has been recommended as a top priority by a group established to advise the Government on future prison capacity needs.

A report by the group has called for the decommissioning of the prison at Arbour Hill in Dublin, which currently houses around 135 long-term prisoners, over the coming decade, although it accepted that it would require “a suitable replacement facility”. 

It has also recommended that priority should be given to returning Mountjoy Prison to single-cell occupancy which would require around 210 prisoners currently housed in shared cells to be accommodated elsewhere.

Given problems with overcrowding across the country’s prison network, the group urged the Government to urgently explore opportunities to accelerate existing plans for large-scale capital projects and recommended fast-tracking such developments by seeking exemptions from normal funding timescales.

It said consideration should be given to prioritising further development of Portlaoise Prison as well as the proposed expansion of the Midlands Prison in Portlaoise.

The report noted there was potential for new prison facilities at Thornton Hall in north Dublin and the redevelopment of the old Cork Prison site.

On Arbour Hill, the report said that despite its drug-free status and low level of assaults, the age of the prison and the fact that the majority of its buildings are protected structures meant the possibilities for future development were “extremely limited”. 

It noted that the prison has a mix of single and double occupancy cells and although in-cell toilet facilities have been provided, they are not partitioned.

The exercise yard in the prison at Arbour Hill; the possibilities for its  future development were “extremely limited”. File picture: Billy Higgins

The report revealed that the country’s prisons were operating at 12% above capacity at the start of 2025, despite some 300 extra prison spaces having been added in recent years.

It also observed that the number of assaults on prisoners by other inmates rose by 31% last year against a background of overcrowding in Irish prisons.

The highest number of people ever in prisons to date was reached this year on April 15 when the prison population was recorded at 5,394 including 276 women.

The official prison capacity at the end of 2024 was 4,531, while it is estimated the prison population is likely to exceed 6,000 by 2035.

The report observed that some of the worst overcrowding is in the two female prisons with the Dóchas Centre in Mountjoy operating at 32% above capacity.

However, the female prison in Limerick is the most overcrowded facility in the network of prisons at 48% above capacity.

For that reason, it recommended that consideration be given to increasing capacity at the two female prisons together with tailored initiatives to support women in the community.

Overcrowding in prisons poses a variety of risks

The report acknowledged that overcrowding in prisons poses a variety of risks including increased violence and assaults on staff and other prisoners and higher levels of contraband as well as unstructured early releases.

It said the Irish Prison Service’s current capital plan had the potential to accommodate 1,100 additional prisoners between 2024 and 2030 if fully funded with 230 expected to be available by the end of the current year.

If fully implemented, it means the prison system will have capacity for 5,614 prisoners by 2030 if all existing prisons remain in use.