Britain's highest court has ruled that evidence obtained under torture cannot be used in British legal hearings.
A panel of seven Law Lords overthrew a decision by Britain's Appeal Court in 2004 that secret tribunals hearing cases relating to the terrorism suspects could consider evidence that would not be acceptable in a British criminal court trial.
That meant UK authorities could consider information that might have been extracted using torture in another country, provided British agents were not directly involved.
The ruling backs the case of eight terrorism suspects and civil rights campaigners.
"I have to conclude that the duty not to countenance the use of torture by admission of evidence in judicial proceedings must be regarded as paramount and to allow its admission would shock the conscience, abuse or degrade the proceedings and involve the state in moral defilement," Lord Carswell said.
The House of Lords ruling comes a day after the United States explicitly banned its interrogators around the world from treating detainees inhumanely after pressure from European governments and the US Congress.