Prisoners who refuse to admit their guilt are punished for it. They serve longer terms with fewer privileges, writes Bob Woffinden

The death of Harold Williams in prison last week was a poignant reminder not just that innocent people can be convicted in Britain but that they are discriminated against in the prison system, which treats the guilty more favourably.

In the first place, the innocent serve longer sentences. Williams, whose case was referred to appeal by the criminal cases review commission last August, was convicted in 1977. He would have been released on parole in 1988 had he been prepared to admit his guilt. That was something he would never do, so he remained a prisoner.

His case is by no means unusual. The solicitor Campbell Malone has a number of clients in the same position, including Neil Edgington, whose case is still with the CCRC. "Neil has been in custody since September 1981, and he had a tariff of 16 years," says Malone. "He has had glowing reports about his conduct in prison, but he has recently been refused both parole and a reduction in his categorisation - because he protests his innocence."

The prison service acknowledges that "it is unlawful to refuse to recommend release solely on the ground that the prisoner continues to deny guilt", but contends that "minimisation and denial of offending are good indicators of continuing risk".

Officially, a prison has to proceed on the basis that the conviction is safe. This is, in principle, the only practical policy, but in practice it will exacerbate the injustice already done to the wrongly convicted prisoner.

There are tremendous incentives for a prisoner to admit guilt. He will be able to earn privileges, which could include more time out of his cell and more visits from his family, and will be able to progress through the system, being re-categorised downwards, in preparation for his ultimate release date.

However this "progress" will be measured by whether he takes part in offending behaviour courses run by psychologists, all of which are predicated on the basis that the prisoner is prepared to admit guilt. If he refuses, he is deemed to be ineligible for the courses and not co-operating with his sentence plan. So he will lose privileges and parole opportunities. This puts otherwise model prisoners in a confrontational position with officers and results in their being labelled "difficult" merely because they assert their innocence.

The issue has long concerned Dr David Wilson, a former prison governor, who is now professor of criminal justice at the University of Central England. "Lots of sceptical prison staff and criminal justice professionals will say dismissively, 'Oh, they all claim to be innocent', but that attitude fails to recognise that prisoners are under constant pressure to acknowledge their guilt, with the temptations of more privileges and an earlier release date, and that it is actually very difficult for a prisoner to continue to assert his innocence."

Another of Malone's clients, Susan May, recently had her case referred to appeal. "At that point, Susan was moved from Durham, where she was settled into a routine, to a different prison, on the basis that there were more courses there that were suitable for her," says Malone.

"The move put her under unnecessary mental pressure at an emotionally difficult time. The idea that she suddenly 'confront her guilt' just when her case had been referred is arrant nonsense.

"You sometimes have to wonder whether there is a deliberate policy to try to break the spirits of prisoners claiming to be innocent."

Prison psychologists generally describe prisoners who protest their innocence as "in denial". However, the setting-up of the CCRC and the Simms and O'Brien judgment at the House of Lords (allowing prisoners to receive visits from the media) were both based on the knowledge that there are innocent people in British prisons.

One prison where matters have come to a head is Frankland in Durham, where 40 prisoners who are protesting their innocence are launching a legal action against the governor. Sharmila Salvi, of the Manchester law firm Olliers, who has taken on the case, explains: "Many prisoners went to Frankland on enhanced status but were downgraded on arrival to standard status because they were not complying with their sentence plan. In other words, they could not take part in offending behaviour courses because to do so would mean admitting guilt."

The relevant prison service order issued by the Home Office says that privilege levels should be "portable" between different prisons and also that targets set in a sentence plan must be "realistically expected of the prisoner".

Privileges that go with enhanced status at Frankland can include all-day visits, television sets, single-cell accommodation and cooking facilities. Salvi says: "We will be arguing that the policy at Frankland is unlawful and discriminatory in respect of prisoners who are asserting their innocence."