The memo provided legal justification for the September 2011 killing in Yemen of Anwar Al-Awlaki, an al-Qaida leader and one-time cleric at a northern Virginia mosque who had been born in the United States, and another U.S. citizen, Samir Khan, who edited al-Qaida's Internet magazine. An October 2011 strike also killed Abdulrahman al-Awlaki, al-Awlaki's teenage son and also a U.S. citizen.
The memo, written by a Justice Department official, said the killing of al-Awlaki was justified under a law passed by Congress soon after the Sept. 11, 2001, terror attacks. The law empowered the president to use force against organizations that planned, authorized and committed the attacks.
Al-Awlaki had been involved in an abortive attack against the United States and was planning other attacks from his base in Yemen, the memo said. It said the authority to use lethal force abroad may apply in appropriate circumstances to a U.S. citizen who is part of the forces of an enemy organization.
The memo stated the Defense Department operation was being carried out against someone who was within the core of individuals against whom Congress had authorized the use of "necessary and appropriate" force. It said the killing was justified as long as it was carried out in accord with applicable laws of war.
The 2nd U.S. Circuit Court of Appeals in Manhattan released the memo, portions of which were blacked out, after the American Civil Liberties Union and The New York Times filed a lawsuit seeking any documents in which Justice Department lawyers had discussed the highly classified "targeted-killing" program. The appeals court ordered the memo disclosed after noting that President Barack Obama and other senior government officials had commented publicly on the subject.
White House spokesman Josh Earnest, responding to criticism from groups that complained that it took a court order to get the memo released, said the administration worked through the legal system "to produce a redacted document that protected national security interests while at the same time trying to live up to our commitment to transparency."
"In this case I think even the groups that sharply criticized us would call this a win for transparency," Earnest said.
Jameel Jaffer, an ACLU lawyer who argued the case before the 2nd Circuit, said the memo will shed light on the administration's reasoning, but "the public still knows scandalously little about who the government is killing and why." He added, "There are few questions more important than the question of when the government has the authority to kill its own citizens."
David E. McCraw, vice president and assistant general counsel for the Times, called the memo "a critical addition to the public debate over targeted killings and should fuel a richer discussion of the legal and security issues that are at the heart of that debate."
The memo was written by David Barron, who at the time was acting chief of the Justice Department's Office of Legal Counsel. He was recently confirmed as a judge in the 1st Circuit Court of Appeals in Boston.
U.S. officials considered al-Awlaki to be an inspirational leader of al-Qaida, and they have linked him to the planning and execution of several attacks targeting American and Western interests, including a 2009 attempt on Christmas Day on a Detroit-bound airliner.
When word leaked out that his name was on a U.S. government "kill or capture" list, his family rushed to court to try to stop the government from killing him, saying he had to be afforded the constitutional right to due process.
Pardiss Kebriaei, a senior attorney with the Center for Constitutional Rights, said the memo's contents showed that the targeted killing program was built on "gross distortions of law."
Kebriaei, who worked with the ACLU on two lawsuits challenging al-Awlaki's killing, estimated that more than 4,000 people may have been killed by drone strikes since 2009.
The lawyer said in a release that although the United States, England and Israel are the only countries that have used drones to kill, other countries soon will have their own armed drones.
"The United States loosening and redefining international rules governing the use of force and war is ultimately not going to make anyone any safer," the lawyer said.
Meanwhile, the 2nd Circuit indicated that the memo's release might not be the last. The appeals court also ordered the Justice Department to show other legal opinions to a lower-court judge to determine whether they also must be disclosed.
In February 2013, the administration released a 16-page Justice Department "white paper" summarizing the legal arguments detailed in the memo released Monday. The paper asserted that it would be legal to kill a U.S. citizen who had joined al-Qaida if "an informed, high-level official" concluded that the person could not be captured and posed "an imminent threat of violent attack against the United States."
The paper offered an expanded definition of "imminence," noting that "an 'imminent' threat of violent attack against the United States does not require ... clear evidence that a specific attack on U.S. persons and interests will take place in the immediate future."
In February, U.S. officials acknowledged that the Obama administration was considering authorizing the CIA or the military to kill another American, this one a militant hiding in Pakistan who allegedly has helped al-Qaida plan attacks against U.S. troops in neighboring Afghanistan. Justice Department lawyers were said to be reviewing the evidence and had not yet determined whether the president should add the American, identified by the New York Times as Abdullah al-Shami, to the so-called "kill list."
A Yemeni human rights activist, Abdel-Rahman Barman, said the memo released Monday shows any security tip that reaches the U.S. government could lead to somebody being killed.
"The U.S. government is already carrying out illegal killings by striking people with drones based on information from security officials," said Abdel-Rahman Barman of Yemen's National Organization for Defending Rights and Freedoms, known as HOOD. "This will only endanger the lives of more people."
Associated Press writers Eric Tucker, Ken Dilianian and White House Correspondent Julie Pace in Washington; Kim Gamel in Kabul, Afghanistan; and Ahmed al-Haj in Sanaa, Yemen, contributed to this report.
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