The make-up of Ireland's prison population had changed significantly in recent years and substantial investment across the prison system is needed in order to keep pace with that change, the director general of the Irish Prison Service, Mr Seán Aylward, has said.
More non-nationals were now being incarcerated and there had also been a marked increase in the number of remand prisoners.
"Those two factors alone would justify some further investment in prison accommodation. Other factors at play include a silting up of the system, with more prisoners now serving much longer sentences, and life sentences.
"We will have to push up the number of beds in order to cope. The silting up factor is only starting to emerge, but now is the time to know it and address it."
Speaking at the annual conference of the Prison Officers' Association in Ennis he said non-nationals were as law abiding as the indigenous community. However, there were more non-nationals in Ireland now than 10 years ago and this was reflected in the prison population.
Many passing through the prison system were being held because of lack of documentation or other immigration-linked matters. Up to date statistics released by the Prison Service yesterday show there were 2,608 committals of non-nationals to prisons last year.
This was an increase of 66 per cent, from 1,039, since 2001. Some 1,800 non-nationals committed last year were held on immigration matters, many only spent a very short period behind bars.
Over 90 nationalities are now represented in the system. Between 5 and 7 per cent of the prison population on any given day was non-national. The increased number of non-nationals in the system had put pressure on bed spaces, Mr Aylward said. The increase in the number of people serving long sentences, including life, increased that pressure.
In 1994 70 prisoners were serving life. This had increased to 118 by 2001 and has climbed even further, to 162, at present. Similarly, the number of remand prisoners had shown a very large increase, from 116 in 1994 to 564 at present.
However, Mr Aylward denied a charge from the POA that jails were so crowded inmates were being offered temporary release to free up beds, in what they termed was "a return to the revolving door system".
He added: "Five years ago one in five of the prison population was on temporary release and a very high proportion of them were on unstructured temporary release.
"Today less than one in 10 are on temporary release, that's a lot less. Most of them or on set out structured programmes which involves entering training or going back to work, so it is structured."
On overcrowding in the prison system, he said the mooted new 1,000-bed Mountjoy Prison would help. There had been 28 offers of sites, all over 100 acres and within 25 kilometres of Dublin, since sites were sought earlier this year. The Office of Public Works was currently evaluating these sites.
The existing Mountjoy complex would be sold for the highest price and the proceeds used to help fund the new facility. The new prison would offer more dignified and humane conditions.
"We do have a difficulty around city centre prisons generally in that it's far too easy for people to throw contraband and even weapons over the wall.
"There is also a problem with these prisons that there is not enough recreation space. Mountjoy was built as a depot, you were held there pending transportation to Australia, it has very small yards and no workshops."