A leading US civil liberties group has obtained a document showing that the former US commander in Iraq sanctioned the abuse that took place in Abu Ghraib prison.
The document, which is published on the American Civil Liberties Union (ACLU) website www.aclu.org, reveals that Lieutenant-General Ricardo Sanchez authorised interrogation techniques using dogs, stress positions, sleep and isolation.
The techniques are against the Geneva Conventions and are forbidden by US army regulations.
Sanchez authorised 29 interrogation techniques in the 2003 memo which was released by the Pentagon under the Freedom of Information Act.
"Presence of Military Working Dogs. Exploits Arab fear of dogs," is one technique listed.
"Yelling, Loud Music, and Light Control. Used to create fear, disorient detainee and prolong capture shock," is another.
In addition to Sanchez's memo, the Pentagon also released 1200 pages of documents which included reports of abuse and sworn statements by troops saying they were ordered to beat prisoners.
US papers uncovered abuses at
Abu Ghraib jail near Baghdad
"General Sanchez authorised interrogation techniques that were in clear violation of the Geneva Conventions and the army's own standards," ACLU attorney Amrit Singh said.
"He and other high-ranking officials who bear responsibility for the widespread abuse of detainees must be held accountable."
ACLU is accusing General Sanchez of perjury after he denied that he had permitted such techniques during a Senate Armed Services Committee in May 2004.
"I never approved any of those measures to be used ... at any time in the last year," he said under oath.
"Lieutenant-General Sanchez's testimony, given under oath before the Senate Armed Services committee, is utterly inconsistent with the written record, and deserves serious investigation," Anthony D Romero, ACLU executive director, said in a letter to attorney-general Alberto Gonzales, asking him to open an investigation into possible perjury.
Romero added: "This clear breach of the public's trust is also further proof that the American people deserve the appointment of an independent special counsel by the attorney-general."
The document contradicts US army and Defence Department claims the Abu Ghraib abuse was carried out by individuals acting without orders.
Those accused of abusing prisoners say they were scapegoats for high-ranking officers and politicians who ordered that detainees be tortured so intelligence gathering in Iraq could be improved.
Charles Graner's lawyer says top
officers countenanced torture
"The government is asking a corporal to take the hit for them," the lawyer of Charles Graner said after his client was given a 10-year prison sentence in January for being a ring-leader in the abuse scandal.
"The chain of command says, 'We didn't know anything about this stuff'. You know that is a lie," the lawyer said.
Reacting to the development, Alaa Shalabi, a senior researcher with the Arab Organisation for Human Rights in Egypt, said the revelations were not a surprise.
"We have proof that these kinds of techniques were practised, especially in Abu Ghraib," he said. "Such actions raise suspicions about the whole chain of command all the way to [US President George] Bush. These practices have been justified by the Pentagon."
Shalabi said he thought abuses were common in all of the detention camps run by the US military.
The US Defence Department said they will respond to the issue in due course of time.