Court bans use of secret evidence in torture cases

London: The Supreme Court has outlawed intelligence services' use of secret evidence in court to conceal allegations that detainees were tortured.

The decision will be seen as a significant victory for open justice, but the panel of nine judges pointed out that parliament could change the law to permit such "closed material procedures" in future.

The appeal was brought by lawyers for MI5 seeking to overturn an earlier appeal court ruling that prevented the service from suppressing accusations British suspects had been ill-treated at Guantanamo Bay and other foreign holding centres.

The case arose out of claims by Bisher Al Rawi, Binyam Mohammad, Jamil Al Banna, Richard Belmar, Omar Deghayes and Martin Mubanga that MI5 and MI6 aided and abetted their unlawful imprisonment and extraordinary rendition.

The five, who deny involvement in terrorism, launched actions for compensation for abuse and wrongful imprisonment. The Guardian, on behalf of a number of media organisations, had intervened in the case to argue in favour of open justice.

In the judgment, all of the judges rejected the security service's main submission that a court has a common law power to order a closed material procedure as an alternative to the more conventional public interest immunity certificate.

Such a power, they argued, would contravene fundamental and long-established principles of open and natural justice.