The moves for one-day-a- week disruption, which falls short of strike action, will add to strains on the prison governors - already struggling with severe overcrowding as the Government's tough law and order policies begin to bite.
But the action is also likely to affect other sections of the criminal justice system as locked-out inmates are likely to be held in police cells and prisoners are likely to be delayed in getting to court.
Jails are currently holding 1,000 more than their official capacity and plans are in hand to open army camps, use ships as floating jails and use police cells, if courts continue to send offenders to prison in unprecedented numbers. An immediate ban on unpaid overtime in the 130 state- run jails will be followed in two weeks by a lock-out of prisoners who have previously been held by police or brought by private escort companies.
John Bartell, chairman of the 25,000-strong Prison Officers' Association, said officers were not prepared to be the 'piggies in the middle' between Mr Howard and Derek Lewis, the service's director- general.
Mr Bartell said it was unacceptable that there had been 4,000 assaults by prisoners, 20 per cent up on the last three years. His members had decided 'they are no longer prepared to have their safety jeopardised'.
The POA action is timed to coincide with today's one-day national strike by 300,000 members of six civil service unions over privatisation.
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