Hundreds of dangerous prisoners given indeterminate sentences could be freed from jail after a court ruled yesterday that holding them longer than their minimum sentence was unlawful.

The High Court judgment was in a test case brought by two inmates serving indeterminate sentences for public protection (IPPs), under which they should be given a risk assessment on entering prison and then allowed to go on courses intended to tackle their offending behaviour before the Parole Board considers them for release.

But the overcrowded prison system has been unable to provide courses for them all, resulting in more than 100 remaining in jail beyond their minimum term. The two offenders complained that, as a result, the Parole Board could not assess whether they still posed a danger to the public when their minimum terms expired.

David Walker, one of the offenders, was given an indeterminate sentence after being convicted of sexual assault while drunk. He is in Doncaster prison, where his minimum tariff expires in October. But he cannot be considered for release until he has gone through the parole procedure, which includes going on a parole course.

Lord Justice Laws, sitting with Mr Justice Mitting, said: “To the extent that the prisoner remains incarcerated after tariff expiry without any current and effective assessment of the danger he does or does not pose, his detention cannot in reason be justified. It is therefore unlawful.”

The judges granted a declaration that Jack Straw, the Justice Secretary, had “acted unlawfully by failing to provide for measures to enable prisoners serving IPP sentences to demonstrate to the Parole Board, by the end of their minimum term, that it is no longer necessary for the protection of the public for them to be confined”.

In the ruling the judges said that IPP prisoners with a minimum term of less than five years were “languishing” in local jails where, according to Anthony Robson, deputy head of public protection at the National Offender Management Service, there were few offending behaviour programmes.

He said: “The stark consequence is that IPP prisoners, or at least a very high proportion of them, at present have no realistic chance of making objective progress. . . towards a real reduction or even elimination of their risk factor by the time their tariff expires.”

If the ruling is upheld, the Prison Service will have to spend millions on offender behaviour programmes for more than 3,000 inmates at a time when it is facing an £80 million cut in its annual budget.

Mr Robson told the court that it would take at least six months after the completion of a review into IPPs before any practical measures could be implemented and a further 18 months before the system to manage them could be fully operative.

David Hanson, the Prisons Minister, said that he had set aside an additional £3 million for extra assessments and offending behaviour programmes.

IPP sentences, introduced in April 2005, are for prisoners assessed as dangerous who have been convicted of one of 153 offences, including affray, assault to resist arrest and riot.

Jack Straw came face to face with the mounting problems facing offenders given the indeterminate sentence for public protection when he made his first jail visit after being appointed Justice Secretary.

Several offenders confronted Mr Straw with the problem after he agreed to meet them during a visit to Belmarsh prison in southeast London. He met inmates who had been kept in jail longer than expected under the tariff imposed by their trial judges. They complained that they had been unable to complete rehabilitation courses because of overcrowding in England and Wales.

Darren McCoo, 41, from Islington, North London, was given an IPP with a minimum term of four years. But while in jail for the past ten months he had been unable to move to a prison where he could go on a course. “The system is so clogged up with so many people that I cannot get a transfer to a jail where there is a course for me,” said McCoo, who was jailed last September for a robbing a cash security van with a machete. He had served an earlier sentence after being arrested for robbery in 1996.

Mr Straw said after his visit that he recognised that there were concerns about the system and pledged to look carefully at the current operation of IPPs.

How IPPs add up

–– 2005 indeterminate sentences to protect public come into force
–– 3,010 prisoners now serving indeterminate sentences
–– 28 median age of those given the sentences
–– 30 months is the median minimum term
–– 173 prisoners on the sentence were beyond minimum term in May

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