Irish Prison Service (IPS) figures show that the number of prisoners on 22/23 hour lock-up in Mountjoy jumped eightfold, from six last October to 47 last month. Prison sources believe that the bloody Kinahan-Hutch feud is behind much of that rise and has increased tensions in the prison.
There have been up to 11 murders in that feud since September 2015. All but one linked to the Kinahan cartel.
Eight occurred between February and August, with a lull in successful attacks until last December, when Noel Kirwan was gunned down in west Dublin.
Tensions have been mounting since then, rising further this year in the run-up to the anniversary of the Regency Hotel attack on February 5, 2016, in which Kinahan cartel lieutenant David Byrne was shot dead.
Two assault rifles and a submachine gun were among 16 firearms linked to the cartel seized in the last week by gardaí.
IPS figures show that 428 prisoners are on some form of restricted regime, compared to 424 last October.
Of those, 397 prisoners (11% of the prison population) were on protection on a selected day in January 2017 — 389 on them at their own request.
There were 72 prisoners on the most isolated of regimes — 22/23-hour lock-up (seven on 23-hour, 65 on 22-hour), compared to 31 last October.
This represents an increase of 41 (132%) on last October. The IPS points out that the figure of 72 is a drop of 65% since 2013. At that stage, the IPS director general set up a high-level group to reduce numbers on restricted regimes and ensure, at a minimum, three hours of out-of-cell time per day.
The figures show that 147 of the 428 people on restricted regimes are incarcerated in Mountjoy Prison — and that 141 of them sought the protection.
Of the 72 prisoners on 22/23-hour lock-up, 47 of them are in Mountjoy, up from six last October.
A further 14 people are on 22/23-hour lock-up in Cloverhill Remand Prison, similar to previous years.
The Irish Penal Reform Trust said 22/23-hour lock-up is a short-term solution with “long term negative consequences”.
Acting executive director Fíona Ní Chinnéide said: “The damaging effects on prisoner mental health have been found to be irreversible after just two weeks in solitary confinement.
“Yet Ireland continues to hold men on 22- and 23-hour lock-up sometimes for more than a year. This practice makes prisons less safe, and will inevitably impact on reintegration post-release.”