On January 17, 2003, Mary Walker, the Air Force general counsel, received an urgent memo from the Pentagon's top attorney. Attached to the classified document was a set of directives drafted two days earlier by Secretary of Defense Donald Rumsfeld.

    "Establish a working group within the Department of Defense to assess the legal, policy and operational issues relating to the interrogations of detainees held by the US Armed Forces in the war on terrorism," the directives said.

    Among the issues to be addressed were "policy considerations with respect to the choice of interrogation techniques, including contribution to intelligence collection, effect on treatment of captured US military personnel, effect on detainee prosecutions, historical role of US armed forces in conducting interrogations, recommendations for employment of particular interrogation techniques by [Defense Department] interrogators."

    John Yoo, then a deputy in the Justice Department's Office of Legal Counsel, drafted the document, dated March 14, 2003. It essentially provided military interrogators with legal cover if they resorted to brutal and violent methods to extract information from prisoners.

    "If a government defendant were to harm an enemy combatant during an interrogation in a manner that might arguably violate a criminal prohibition, he would be doing so in order to prevent further attacks on the United States by the al Qaeda terrorist network," Yoo wrote. "In that case, we believe that he could argue that the Executive Branch's constitutional authority to protect the nation from attack justified his actions."

    The legal opinion for military interrogators was virtually identical to an earlier memo that Yoo had written in August 2002 for CIA interrogators. Widely called the "Torture Memo," it provided CIA interrogators with the legal authority to use long-outlawed tactics, such as waterboarding, when interrogating so-called high-level terrorist suspects.

    But Yoo did not work on the legal opinions alone.

    Pentagon Frustrations

    In early January 2003, commanders stationed at Guantanamo Bay prison in Cuba complained to Rumsfeld that military officials were unable to glean information from prisoners about alleged terrorist plots in the US and abroad using conventional interrogation methods.

    Following his conversation with military officials, on January 15, 2003, Rumsfeld sent William Haynes II, the Pentagon's general counsel, a memo requesting that he form a "working group" to determine what methods military interrogators could use to extract information from a prisoner at Guantanamo Bay.

    Haynes asked the Justice Department's Office of Legal Counsel for guidance and selected Walker to chair a "working group" to write a report on legally permissible interrogation techniques.

    The members of the group included former Undersecretary of Defense for Policy Douglas Feith, officials from the Defense Intelligence Agency, representatives of the Joint Chiefs of Staff, and judge advocate generals (JAGs) from all four branches of the military.

    By the time Walker's group had settled in for its first meeting, interrogators at Guantanamo Bay had already begun to violate the Geneva Conventions.

    To ratchet up pressure on prisoners, US military personnel were experimenting with unusual tactics, including placing women's underwear on prisoners' heads, a technique that later reappeared in Iraq's Abu Ghraib prison.

    A military official, who took part in discussions with Walker's group, told The Wall Street Journal in June 2004 that there was a growing frustration among interrogators.

    "We'd been at this for a year-plus and got nothing out of them," the official said, adding that threats were even made against the families of detainees.

    The official said the message to a detainee would be: "I'm on the line with somebody in Yemen and he's in a room with your family and a grenade that's going to pop unless you talk."

    Framing the Debate

    While Walker's report was being drafted, the group discussed 35 different interrogation techniques that could be used to obtain information from prisoners.

    Early drafts of the report advocated intimidating prisoners with dogs, removing prisoners' clothing, shaving their beards, slapping prisoners in the face and waterboarding.

    Though some of the more extreme techniques were dropped as the list was winnowed down to 24 from 35, the final set of methods still included tactics for isolating and demeaning a detainee, known as "pride and ego down."

    Such degrading tactics violated the Geneva Conventions, which bars abusive or demeaning treatment of captives.

    The more extreme interrogation methods that made it into the final draft of the report rankled some of the JAGs, who feared the methods would put US soldiers in danger if they were captured - and would tarnish the reputation and image of the US abroad.

    "Will the American people find we have missed the forest for the trees by condoning practices that, while technically legal, are inconsistent with our most fundamental values," wrote Rear Adm. Michael Lohr, a member of the "working group," in a February 2003 letter to Walker.

    "How would such perceptions affect our ability to prosecute the Global War on Terrorism?" asked Lohr.

    The admiral was so upset with the draft report and the advice provided by the Justice Department that he requested Walker include a sentence in the final report making it clear that the legal findings were based exclusively on attorneys in the Justice Department's Office of Legal Counsel.

    Lohr was not alone. Maj. Gen. Jack Rives, who at the time was judge advocate general of the Air Force, also wrote a letter to Walker warning that the interrogation techniques in the report would violate military law.

    "Several of the exceptional techniques, on their face, amount to violations of domestic criminal law and the [Uniform Code of Military Justice]," Rives wrote. "Treating detainees inconsistently with the [Geneva] Convention arguably 'lowers the bar' for the treatment of US POW's in future conflicts."

    Maj. Gen. Thomas Romig, an Army JAG, and Brig. Gen. Kevin M. Sandkuhler, a Marine Corps JAG, also voiced concerns, specifically the determination that the president has the power to override the Uniform Code of Military Justice and other federal statutes and international treaties in the name of national security.

    Defending Bush's Authority

    Walker's group addressed these concerns, according to the report, by stating, in legal terms, that the president had the constitutional authority as commander in chief to ignore torture laws if national security were in jeopardy.

    On March 6, 2003, eight days before Yoo issued his legal opinion, Walker sent Rumsfeld a draft 53-page "working group" report that said international treaties forbidding torture did not apply to prisoners held at Guantanamo Bay.

    The report, which asserted that President Bush had "sweeping" powers as commander in chief, said Bush could suspend international laws and treaties governing torture in the name of national security.

    "In order to respect the President's inherent constitutional authority to manage a military campaign ... (the prohibition against torture) must be construed as inapplicable to interrogations undertaken pursuant to his Commander-in-Chief authority," the report stated.

    The Justice Department could not prosecute military interrogators "who had acted pursuant to an exercise of the President's constitutional power," the report added.

    Further, the report said that if a prisoner died as a result of a brutal interrogation technique, the interrogator would not be subject to prosecution if he had acted in a "good faith" effort to save lives.

    "Good faith may be a complete defense," the report said. "Sometimes the greater good for society will be accomplished by violating the literal language of the criminal law."

    The report cited a legal text, "Substantive Criminal Law" by Wayne LaFave and Austin W. Scott, to support the legality of the interrogation methods: "In particular, the necessity defense can justify the intentional killing of one person ... so long as the harm avoided is greater."

    Rumsfeld signed the final report on April 2, 2003, two weeks after Bush ordered US forces to invade Iraq.

    One year later, photos depicting US soldiers abusing and humiliating detainees at Abu Ghraib prison in Iraq were publicly released.

    Congressional Reaction

    The tide began to turn against Yoo's and Walker's expansive attitudes toward presidential authority when Jack Goldsmith took over as chief of the Office of Legal Counsel and, by early 2004, had rescinded Yoo's opinions.

    On June 15, 2004, the Senate passed an amendment to the Defense Authorization Bill backed by Republican Sen. Lindsay Graham, to give JAGs the same legal authority as military attorneys, like Walker, who are appointed by the president.

    The amendment, dubbed the "Mary Walker bill," was spurred by complaints from JAGs, who said Walker had ignored their legal concerns about the interrogation of detainees at Guantanamo Bay.

    In February 2008, the Justice Department's Office of Professional Responsibility (OPR) confirmed that it had launched a formal investigation into whether Yoo and other attorneys in the Office of Legal Counsel gave the White House poor legal advice in authorizing CIA interrogators to use waterboarding to glean information about terrorist plots from prisoners.

    In effect, the legal opinions from Walker and Yoo sought to provide a basis for the Bush administration to circumvent US and international laws prohibiting torture of prisoners.

    Immediately after the 9/11 attacks, the United Nations Committee Against Torture reaffirmed the prohibitions contained in the 1984 Convention Against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment.

    The Convention - approved by 145 nations, including the United States - states that "no exceptional circumstances whatsoever, whether a state of war or a threat of war, internal political instability or any other public emergency, may be invoked as a justification of torture."

    Moreover, the convention says individuals who resort to torture cannot defend their actions by saying they were acting on orders from superiors.

    The United States signed the Convention Against Torture in 1988 under President Ronald Reagan, who hailed it as "a significant step" in preventing torture, which he called "an abhorrent practice unfortunately still prevalent in the world today."

    In a May 20, 1988, message to the US Senate, Reagan noted that "the core provisions of the Convention establish a regime for international cooperation in the criminal prosecution of torturers relying on so-called 'universal jurisdiction.'

    "Each state party is required either to prosecute torturers who are found in its territory or to extradite them to other countries for prosecution."

    It was this Convention, ratified by the Senate in 1994, that Walker, Yoo, and other Bush administration officials sought to bypass.

    Although the treaty mandates that the United States cooperate in the criminal prosecution of torturers, the administration's post-9/11 legal opinions sought to shield American interrogators.

    The Walker report, which was tailored to fit with Yoo's legal arguments, advised military interrogators that they could defend their actions by saying Justice Department lawyers told them that their methods were legal.