An MI5 expert in terrorism has admitted that the security service would use information extracted from tortured prisoners as evidence in court.
The secret witness told a panel of judges that in spite of knowing that a victim had been tortured or had come from a country where the regime sanctioned torture, she would still consider their testimony to be relevant to security service investigations.
The admissions will add to growing public concern over the detainees at Guantanamo Bay in Cuba, who were questioned by the CIA and by MI5 officers. Critics claim that the government has condoned torture by the US in its attempts to garner evidence against people it suspects of having been involved in al-Qaida or the Taliban.
The implication of the testimony has shocked human rights campaigners, as well as lawyers and the families of those detained. Article three of the Human Rights Act says "no one shall be subjected to torture or inhuman or degrading treatment or punishment".
Malcolm Smart, director of the Medical Foundation for the Care of Victims of Torture, criticised the government for being party to torture, "either directly or by proxy".