With the prison population in England and Wales at a record 59,156 last Friday, there are only 700 places left, and inmates are being bused around the country to try to find them a bed for the night.
The scale of the problem was underlined by Chris Scott, chairman of the Prison Governors' Association (PGA), who told his annual conference that jails could not cope with a population which had gone "through the roof". He also voiced concerns about proposed emergency measures, which include the use of a prison ship in Portland harbour, Weymouth, and the conversion of a former holiday camp in Lancashire.
Both schemes are being opposed by local planners.
Speaking at the conference at Buxton, Derbyshire, Mr Scott said: "Surely it is sensible to admit that we can no longer cope with this unprecedented rise. In normal circumstances no one in their right mind would seriously consider the introduction of prison ships and abandoned holiday camps as prison accommodation.
"The Prison Service has reached the crossroads where policy and operations meet. Those responsible when there is a new prison disaster will be those who have refused to accept that our prisons are full to the brim and can accept no more. Prison governors should not and will not be held accountable when this inevitable crisis occurs. There have to be measures to ensure that prison is used solely for the persistent offender and the most serious offender."
He called for the Prison Service's population problems to be referred to the Criminal Justice Consultative Council, a forum made up of representatives from all the agencies in the criminal justice system.
David Roddan, secretary of the PGA, said:"Last week 134 prisoners were bused from the north of England to the south to find empty cells; that is crazy. The prison population is increasing by up to 400 a week. We are talking about a day-to-day struggle to find empty beds for prisoners. The Prison Service is chock-a-block. If the police had a purge on a particular kind of offender, we couldn't cope."
Linda Jones, chairwoman of the Association of Chief Officers of Probation, said existing community-based sentences should be used more widely to help alleviate the population pressures.
The prisons minister, Ann Widdecombe, who addresses the PGA conference today, said 8,000 new prison places were being built. "It's nothing short of a miracle that despite the huge and unprecedented increase in numbers, we haven't ended up in police cells."
However, it is understood the Prison Service is preparing to use 1,200 police cells in England and Wales.Reuse content