WASHINGTON — The Justice Department in 2003 gave military interrogators broad authority to use extreme methods in questioning detainees and argued that wartime powers largely exempted interrogators from laws banning harsh treatment, according to a memorandum publicly disclosed on Tuesday.
In a sweeping legal brief written in March 2003, when the Pentagon was struggling to determine the appropriate limits for its interrogators, the Justice Department gave the Pentagon much of the same authority it had provided to the Central Intelligence Agency in a memorandum months earlier. Both memorandums were later rescinded by the Justice Department.
The disclosure of the 2003 document, a detailed 81-page opinion written by John C. Yoo, who at the time was the second-ranking official at the Office of Legal Counsel at the Justice Department, is likely to fuel the already intense debate about legal boundaries in the face of a continuing terrorist threat.
Mr. Yoo’s memorandum is the latest document to illuminate the legal foundation that Bush administration lawyers used after the attacks of Sept. 11, 2001, to give the White House broad powers to capture, detain and interrogate suspects around the globe.
The thrust of Mr. Yoo’s brief has long been known, but its specific contents were revealed on Tuesday after government lawyers turned it over to the American Civil Liberties Union, which has sought hundreds of documents from the Bush administration under the Freedom of Information Act.
Some legal scholars said Tuesday that they were amazed at the scope of the memorandum.
“This is a monument to executive supremacy and the imperial presidency,” said Eugene R. Fidell, who teaches military justice at Yale Law School and the Washington College of Law at American University. “It’s also a road map for the Pentagon for fending off any prosecutions.”
The memorandum gave the military broad latitude to use harsh interrogation methods. It reasoned that federal laws prohibiting assault were not applicable to military interrogators dealing with members of Al Qaeda because of White House authority during wartime. It also argued that many American and international laws would not apply to interrogations overseas.
“Even if an interrogation method arguably were to violate a criminal statute, the Justice Department could not bring a prosecution because the statute would be unconstitutional as applied in this context,” it reads.
Justice Department lawyers later rescinded both Mr. Yoo’s memorandum and the similar one written for the C.I.A. in August 2002. In a book published last year, Jack Goldsmith, who as head of the Office of Legal Counsel made the decision to rescind the memorandums, criticized the documents, saying they had used careless legal reasoning to provide national security agencies with sweeping interrogation authority.
Written to William J. Haynes II, who at the time was the Pentagon’s general counsel, Mr. Yoo’s document was meant to give legal guidance to Defense Department lawyers as they wrestled with a list of interrogation methods for prisoners at the military prison at Guantánamo Bay, Cuba.
The document explains that Mr. Haynes had asked the Justice Department “to examine the legal standards governing military interrogations of alien unlawful combatants held outside the United States.”
The Pentagon was trying to set clear guidelines for military interrogators after Donald H. Rumsfeld, the defense secretary at the time, withdrew approval for some interrogation techniques opposed by some senior military lawyers.
Ultimately, Mr. Yoo’s memorandum provided the legal foundation for the group’s final report, which defended the use of harsh interrogation methods.
Similar to the document written for the C.I.A. in August 2002, Mr. Yoo’s memorandum offered a narrow definition of what constitutes torture.
“The victim must experience intense pain or suffering of the kind that is equivalent to the pain that would be associated with serious physical injury so severe that death, organ failure or permanent damage resulting in a loss of significant body functions will likely result,” Mr. Yoo wrote.
Despite the wide latitude the document gave to the military, the Pentagon never authorized some of the harshest interrogation methods used by the C.I.A., including waterboarding, a simulated drowning technique.
Amrit Singh, a lawyer for the American Civil Liberties Union, said that the Yoo memorandum seemed to give military interrogators “carte blanche” to use any techniques and suggested that it was the legal underpinning for abuses that occurred months later at the Abu Ghraib prison in Iraq.
No Pentagon investigations have found that any senior Bush administration officials were complicit in the abuse at Abu Ghraib.
The investigations did find, however, that for several years after the Sept. 11 attacks, the Pentagon failed to set uniform standards for military interrogations worldwide.
Martin S. Lederman, a former lawyer for the Office of Legal Counsel who now teaches at Georgetown University, noted Tuesday night on the legal blog Balkinization that Mr. Yoo’s memorandum was issued on a Saturday one day after his boss, Jay S. Bybee, left the Justice Department.
Some legal experts and civil liberties groups have for years criticized the August 2002 memorandum written for the C.I.A. as overly expansive in the authority it gave the agency to interrogate detainees.
That memorandum was also written by Mr. Yoo, who is now a law professor at the University of California, Berkeley, but it was signed by Mr. Bybee and for several years has been commonly known as the Bybee memo.
The document provided a legal foundation for coercive techniques used later against other high-ranking detainees, like Khalid Shaikh Mohammed, who is believed to be the chief architect of the Sept. 11 attacks and was captured in early 2003.
The Detainee Treatment Act passed by Congress in 2005 required the Defense Department to restrict interrogation methods to those set out in the Army Field Manual, which bans coercive interrogations.
Last year, President Bush issued an executive order narrowing the list of approved techniques for the C.I.A. Intelligence officials have said that waterboarding is not on the list of currently approved techniques but that President Bush could authorize its use during an emergency.