WASHINGTON — A senior United Nations official said on Wednesday that the growing use of armed drones by the United States to kill terrorism suspects was undermining global constraints on the use of military force. He warned that the American example would lead to a chaotic world as the new weapons technology inevitably spread.
In a 29-page report to the United Nations Human Rights Council, the official, Philip Alston, the United Nations special representative on extrajudicial executions, called on the United States to exercise greater restraint in its use of drones in places like Pakistan and Yemen, outside the war zones in Afghanistan and Iraq.
The report — the most extensive effort by the United Nations to grapple with the legal implications of armed drones — also proposed a summit meeting of “key military powers” to clarify legal limits on such killings.
In an interview, Mr. Alston said the United States appeared to think that it was “facing a unique threat from transnational terrorist networks” that justified its effort to put forward legal justifications that would make the rules “as flexible as possible.”
But that example, he said, could quickly lead to a situation in which dozens of countries carry out “competing drone attacks” outside their borders against people “labeled as terrorists by one group or another.”
“I’m particularly concerned that the United States seems oblivious to this fact when it asserts an ever-expanding entitlement for itself to target individuals across the globe,” Mr. Alston said in an accompanying statement. “But this strongly asserted but ill-defined license to kill without accountability is not an entitlement which the United States or other states can have without doing grave damage to the rules designed to protect the right to life and prevent extrajudicial executions.”
Mr. Alston is scheduled to present his findings to the Human Rights Council in Geneva on Thursday. While not legally binding, his report escalates the volume of international concerns over a tactic that has become the Obama administration’s weapon of choice against Al Qaeda and its allies.
The New York Times reported last week that Mr. Alston’s report would call on the United States to stop using Central Intelligence Agency-operated drones and limit the technology to regular military forces because they are open and publicly accountable for their conduct — for example, by investigating missile strikes that kill civilians.
Days later, news emerged that a C.I.A. drone strike in Pakistan’s tribal areas was believed to have killed Al Qaeda’s third-ranking leader, apparently a major success. In an interview on Wednesday, Mr. Alston acknowledged that the United States could make “a reasonable legal argument” that a strike against such a figure in those circumstances was lawful and appropriate, but he argued that the escalating number of drone strikes in Pakistan still raised concerns.
The recent strike “is a very convenient one because there you have got a very clearly acceptable target, but we’re not told who the other strikes are against and what efforts are being made to comply with the rules,” he said.
The report calls on nations like Pakistan to publicly disclose the scope and limits of any permission granted for drone strikes on their territories. It also calls on drone operators like the United States to disclose the legal justification for such killings, the criteria and safeguards used when selecting targets, and the process for investigating attacks that kill civilians.
A White House spokesman declined to comment on the report, but pointed to a speech in March by the State Department legal adviser, Harold Koh, that partly outlined the Obama administration’s legal rationale. Mr. Koh said the United States obeyed legal limits on the use of force when selecting targets, and he defended drone killings as lawful because of the armed conflict with Al Qaeda and because of the nation’s right to self-defense.
“A state that is engaged in an armed conflict or in legitimate self-defense is not required to provide targets with legal process before the state may use lethal force,” he said. “Our procedures and practices for identifying lawful targets are extremely robust, and advanced technologies have helped to make our targeting even more precise.”
The United Nations report agrees that drone killings can be lawful in battlefield combat. But it says that the United States is stretching the limits of who can be lawful targets.
For example, it criticized the United States for singling out drug lords in Afghanistan suspected of giving money to the Taliban, a policy it said was contrary to the traditional understanding of the laws of war. Similarly, it said, terrorism financiers, propagandists and others who are not fighters should face criminal prosecution, not summary killing.
It also said that a targeted killing outside of an armed conflict “is almost never likely to be legal.” In particular, it rejected “pre-emptive self-defense” as a justification for killing terrorism suspects far from combat zones.
“This expansive and open-ended interpretation of the right to self-defense goes a long way towards destroying the prohibition on the use of armed force contained in the U.N. Charter,” Mr. Alston said. “If invoked by other states, in pursuit of those they deem to be terrorists and to have attacked them, it would cause chaos.”
But a United States official, speaking anonymously because of the sensitivity of the issue, said drone attacks had been an “effective, exact and essential” tactic for reaching militants in inaccessible areas of Pakistan, whose government does not want the United States military fighting in its territory.
“The United States has an inherent right to protect itself and will not refrain from doing so based on someone else’s exceptionally narrow — if not faulty — definition of self-defense,” the official said. The report noted that Russia and Israel had also claimed a right in recent years to single out people they deemed terrorism suspects, and Mr. Alston said 40 other countries already had drone technology — with several already seeking armed versions.
Warning that the technology is making targeted killings much easier and more frequent, the report urged major military nations to meet with human rights specialists to work out agreements on murky legal issues, such as when a farmer who sets roadside bombs at night may be a target.
The report also raised concerns that drone operators might not have the same respect for the laws of war as soldiers in the field who have “been subjected to the risks and rigors of battle.”
“Because operators are based thousands of miles away from the battlefield, and undertake operations entirely through computer screens and remote audio-feed, there is a risk of developing a ‘PlayStation’ mentality to killing,” it said.
Last week, the military released a report faulting military drone operators for “inaccurate and unprofessional” reporting that led to an airstrike in February that killed 23 Afghan civilians, including women and children.