WASHINGTON: A newly revealed Justice Department memo finds that US citizens believed to be senior al Qaeda operators may lawfully be killed, even if no intelligence shows they are actively plotting an attack.
The disclosure by NBC News, which posted a link to the white paper on its web page, comes amid rising controversy over US use of drone strikes to kill al Qaeda suspects in Pakistan and Yemen.
Among the most controversial were the September 2011 killings in Yemen of Anwar al-Awlaki and Samir Khan, whose killings stoked concern because they were US citizens who had never been charged with a crime.
The white paper offers a more expansive definition of self-defense and imminent attack than those given publicly in the past by senior US officials, who have cited "the inherent right to self-defense" in defending the attacks.
"The condition that an operational leader present an 'imminent' threat of violent attack against the United States does not require the United States to have clear evidence that a specific attack on US persons and interests will take place in the immediate future," the memo says.
Instead, an "informed, high-level" official could decide that the targeted individual posed "an imminent threat of violent attack against the United States" if he had "recently" engaged in such activities and there was no evidence he had renounced or abandoned them.
The memo also says the individual's capture must be infeasible, and can be considered so if capture posed an "undue risk" to US personnel.
The 16-page memo is entitled "Lawfulness of a Lethal Operation Directed Against a US Citizen Who Is a Senior Operational Leader of al Qaeda or An Associated Force."
NBC said the memo was given to the Senate Intelligence and Judiciary Committees in June on condition it be kept confidential and not discussed publicly.
Its leak comes just two days before White House counter-terrorism chief John Brennan goes before the Senate for hearings on his nomination to be head of the CIA.
Brennan has been a central player in the US drone campaign, which has expanded sharply under President Barack Obama despite qualms about its legality and public outrage in Pakistan over civilian deaths.
Jameel Jaffer, deputy legal director of the American Civil Liberties Union, which has sued to obtain the legal document used to authorize the killing of Awlaki, a radical preacher, called the white paper "chilling."
"According to the white paper, the government has the authority to carry out targeted killings of US citizens without presenting evidence to a judge before the fact or after, and indeed without even acknowledging to the courts or to the public that the authority has been exercised.
"Without saying so explicitly, the government claims the authority to kill American terrorism suspects in secret," he wrote on the ACLU's web site.
Administration officials fiercely defend the drone program as key to the US strategy against al Qaeda, in a war against terrorism with no geographic boundaries.
"It's been an important part of our operations against al Qaeda, not just in Pakistan, but also in Yemen, in Somalia and I think it ought to continue to be a tool we ought to use where necessary," outgoing US Defense Secretary Leon Panetta said in an interview with AFP last week.