Jack Straw’s control of the prison system was dealt a fresh blow yesterday after the High Court ruled that the Parole Board was in breach of the law because it is too close to the Government.

Although the Justice Secretary is seeking an immediate appeal, the ruling could result in the removal of the board from the Ministry of Justice to ensure its independence.

In a case brought by four prisoners, the High Court in London ruled that the present arrangements - in which the board has close relations with the Ministry of Justice - “do not sufficiently demonstrate its objective independence” as required by human rights law.

The prisoners are fighting for release from custody and they argued that their right to a fair hearing had been violated because of the board’s close links with the Government.

Lord Justice Hughes and Mr Justice Treacy said that they had found no sign of any undue influence on individual cases. But they ruled that “the present arrangements for the Parole Board do not sufficiently demonstrate its objective independence of the Secretary of State, as required by English common law and the European Convention on Human Rights”. Under the convention a detained person is entitled to a speedy hearing before an independent tribunal to determine whether detention is lawful.

John Dickinson, a solicitor for the prisoners, said of the ruling: “If it is upheld on appeal, this judgment will affect not only tens of thousands of prison inmates but all those who rely on Parole Board decisions.

“This issue of the Parole Board not being sufficiently independent of the Government was emphasised by its description in a Home Office review as being ‘an instrument of Government policy’. The court found that the influence and control that the Secretary of State has over the board fatally undermines its required perception of independence.”

A spokeswoman for the Ministry of Justice said: “This judgment will not result in any prisoner being released earlier than would otherwise have been the case, neither does it open the way for offenders to seek to apply for compensation.

“The court was clear that there was no evidence of the department seeking to influence the Parole Board in individual cases or that Parole Board members were unduly influenced by the department.” She added: “The Parole Board has a difficult and important responsibility of risk assessing the most dangerous offenders.”

If Mr Straw loses on appeal, the Parole Board’s close links with the Justice Secretary will be severed and the board may be placed under the Courts Service or made a freestanding quango.

A spokesman for the board said: “Unless the decision is reversed on appeal, this means that the Secretary of State will have to take the necessary steps to ensure that the board does become sufficiently independent, or risk being in contempt of the court.

“Those steps might include moving the sponsorship of the board to a government department that is not party to the proceedings of the board, as the Ministry of Justice is in its role as the department responsible for the National Offender Management Service.

“It might alternatively involve the board, as a court, becoming part of Her Majesty’s Courts Service.”

The scale of the board’s work and the number of prisoners that could be affected by any restructuring were reflected in the judges’ observation that, in 2002, the board made more than 14,000 decisions.

Human rights lawyers had complained in court about the Government’s refusal to fund board interviews with prisoners as part of the risk-assessment procedure, which is necessary when decisions were made on parole eligibility.

They also accused the Government of wrongly making rules as to the manner in which the board conducted reviews.

Yesterday the judges endorsed their concern over the “closeness” between the board and Mr Straw’s department. In particular the judges highlighted a speech made last year by Charles Clarke, then Home Secretary, in which he intended to alter the composition of the board membership.

Mr Clarke announced that he wanted to appoint new members “with experience either of being a victim of crime or of involvement with a victim support organisation”. The judges said that Mr Clarke’s announcement came when there was public anxiety about reoffending by released prisoners.

Mr Clarke’s proposals were “designed to alter, to some extent at least, the outcome of cases before the board”. The judges said that such a power was “inconsistent with the objective appearance” of the board’s independence and “came more easily to hand because the board exists as a sponsored unit within the appointing minister’s Department of State”.

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