At the beginning of July 1999, the law lords, headed by Lord Steyn, decided that it was unlawful to stop inmates talking to the media (see article from Guardian below).

One of the prisoners - Michael O'Brien - had his conviction for murder quashed in December 1999; the other - Ian Simms - is still in prison.

The full text of the law lords' judgment in this case is published at the Stationery Office Web site.

More than four years ago, two prisoners began a legal battle over inmates' right to talk to the media. Bob Woffinden, one of the journalists banned from telling their stories, reports as the fight reaches the House of Lords...

Tomorrow the House of Lords will begin hearing an important case on freedom of speech, which will decide what rights prisoners have to receive visits from journalists. The legal action originated over four years ago with a terse letter from the Prison Service to me. Now, the case material amounts to uncounted numbers of files, and teams of lawyers stand ready to dispute the issue before the highest court in the land.

The prison rules were drawn up in 1964: standing order five, and in particular paragraphs 37 and 37a, stipulate journalists should be allowed to visit prisoners only on condition that they sign an undertaking not to disclose or publish any information obtained during the visit.

In practice, journalists have routinely met prisoners at normal visiting times, gathered information and used it as they wished. And it used to be only blatant breaches of the code that caused problems: for example, when Chris Mullin smuggled in a tape-recorder to record the protestations of innocence of some of those convicted of the Birmingham pub-bombings; or when Central TV managed to circumvent normal procedures to film an interview with the murderer Dennis Nilsen.

In that case, in 1993, the High Court and the Court of Appeal rejected attempts by the Home Office to prohibit the transmission of the interview. By 1995, however, even the most elementary technology - pen and paper - was too great a threat to the authorities. After I reported a number of cases which I perceived to be miscarriages of justice (a perception which, in many instances, the Court of Appeal came to share), the then Home Secretary, Michael Howard, referred the matter of my visits to the director general of the Prison Service. I was told I could visit as a friend, but only if I signed the not-to-publish undertaking.

This created a problem. Can you, as a friend, visit someone you believe has suffered serious wrong and yet, as a journalist, pledge not to bring this to public attention? What kind of friend are you deliberately not to use the means at your disposal to advance his cause? What kind of journalist lays down his pen in the face of injustice?

Then there were wider considerations. Article 10 of the European Convention on Human Rights (now being incorporated into British law) lays down: 'Everyone has the right to freedom of expression. This right shall include freedom to hold opinions and to receive and impart information and ideas without interference by public authority.'

This should not exclude prisoners. The House of Lords ruled in 1983 that prisoners retained all basic rights, except those necessarily taken away as a consequence of their imprisonment. A prisoner may wish to make representations about his own or other inmates' cases or observations about judicial processes, or to pass on information about life inside. All would be valid concerns. We have heard a lot recently about prison conditions both the unacceptable, from Sir David Ramsbotham, chief inspector of prisons; and the even more unacceptable, like the brutal treatment of inmates alleged against 43 prison officers at Wormwood Scrubs which should have come to public notice sooner.

Ian Simms, the prisoner I could visit only if I undertook not to write about his case, sought judicial review of the Home Secretary's actions on the grounds that his freedom of expression had been infringed. His case was joined with that of Michael O'Brien, who had been denied visits from a BBC producer.

Both men asserted their innocence. O'Brien has since had his case referred to appeal by the Criminal Cases Review Commission, and has been released on bail; Simms's case is still being considered.

The Home Office originally argued that the enforcement of paragraphs 37 and 37a was essential to protect 'the legitimate interests of the public, including the victims of crime' and 'to prevent gratuitous details of a prisoner's offence entering the public domain'. It added: 'There would be serious risk of distress to victims and their families and general public outrage at the sight of prisoners and [journalists] collaborating to publish details of a prisoner's case.' I believe nothing derived from prison interviews has or would ever compromise 'the legitimate interests of the public', much less foment 'general public outrage'.

The official approach seemed inconsistent. In 1998, a Mirror reporter interviewed Bruce Childs, a prisoner who 'confessed' to more murders than he had already been convicted of. The Mirror gave this the front page and generous space inside. Childs had told contradictory stories down the years, and is known as a man of precarious mental balance. No one should accept his uncorroborated statements. The Mirror splash had less to do with the search for truth than the search for sensation; yet no one in official circles expressed concern for the bereaved.

The other Home Office argument was that access to the media could be achieved through correspondence. This would carry little weight with most prisoners. Letters can and do get lost. Some inmates may find difficulty in writing, or even be illiterate and letters in and out of prison are screened. Prisoners prefer not to put sensitive, or potentially key, aspects of their case down in writing.

In 1996, Mr Justice Latham ruled that paragraphs 37 and 37a were unlawful. A year later, this decision was reversed at the appeal court when Lord Justice Kennedy held that 'a convicted prisoner has no right to communicate orally with the media through a journalist'.

The decisive round now begins at the Lords. Lawyers for Simms and O'Brien will explain that the European Court of Human Rights in Strasbourg has already plainly stated that its duty is to guarantee 'not rights that are theoretical or illusory, but rights that are practical and effective'.

If freedom of expression is not to be illusory, it must encompass the freedom to express views in person to the media. Yet the consequence of the Home Office's demand for a not-to-publish undertaking is that journalists will not visit; so, the right to communicate with a journalist is taken away and prisoners are deprived of freedom of expression.

A ban by the home secretary on journalists visiting prisoners and writing about their cases was an unlawful interference with free speech, five law lords declared yesterday.

The judges said that prisoners who protested their innocence often had no other means of searching out the fresh evidence needed to have their cases looked at again.

Lord Steyn said: "In recent years a substantial number of miscarriages of justice have only been identified and corrected [through] painstaking investigation by journalists."

The law lords, who were given details of 60 cases, unanimously overturned an appeal court ruling that the ban was justified. Lord Steyn added: "The criminal justice system has been shown to be fallible. Yet the effect of the judgment of the court of appeal is to outlaw the safety valve of effective, investigative journalism."

Lords Browne-Wilkinson, Steyn, Hoffmann, Hobhouse and Millett declared unlawful the home secretary's policy of banning media visits. They also said the prison governors' refusal to allow journalists interviews with inmates unless they agreed not to write about cases, was unlawful.

The appeal was brought by Ian Simms, now in Long Lartin prison, serving a life sentence for murder, and Michael O'Brien, a convicted murderer now out on bail pending a new appeal.

Bob Woffinden, an investigative journalist who writes for the Guardian, and Karen Voisey, a BBC Wales producer, had been refused permission to visit Simms and O'Brien respectively unless they agreed to sign the undertaking.

The law lords were strongly influenced by an affidavit from Gareth Peirce, a solicitor who has acted for more than 20 miscarriage of justice victims. She told the judges there was no legal aid for investigations and that more than 90% of applicants to the Criminal Cases Review Commission had no solicitor. Cases with the best chance of being taken up were those which "arrive at the commission fully researched and investigated with new evidence compellingly presented". The resources available to television and the national and local press provided the best chance of discovering new evidence, she added.

Lawyers for Jack Straw, the home secretary, had argued that allowing visits would harm prison discipline, and that stories related in the media would upset relatives of the crime victims.

The ban was imposed in 1995 after Michael Howard, then home secretary, received a complaint from an MP representing Marie McCourt, the mother of Helen, whom Simms was convicted of murdering.

Before then, said Lord Steyn, interviews with prisoners "had served to identify and undo a substantial number of miscarriages of justice". He said: "The evidence establishes clearly that without oral interviews it is now virtually impossible, under the ban, for a journalist to take up the case of a prisoner who alleges a miscarriage of justice - a means of correcting errors in the functioning of the criminal justice system has been lost."

Lord Steyn said that freedom of speech was "the lifeblood of democracy" acting "as a brake on the abuse of power by public officials".

But Mrs McCourt, whose daughter's body has not been found, said: "Prisoners should not have the privilege of contact with journalists [to] publicise either their cases, for monetary gain or to boost their egos and self esteem."