Defending armed drone use by calling them a valid response to the Sept. 11, 2001, terrorist attacks on the United States is unjustifiable, Christof Heyns, United Nations special rapporteur on extrajudicial, summary or arbitrary executions, told a U.N. Human Rights Council conference in Geneva, Switzerland, after Russia and China issued a joint statement to the council condemning drone attacks.
New technologies that improve remote drone operators' ability to engage easily in combat in far-flung regions has led to growing diplomatic and non-governmental concerns about civilian casualties and about other countries also acquiring drones, The New York Times reported.
Some countries "find targeted killings immensely attractive," said Heyns, a South African human-rights law professor. "Others may do so in future."
Current drone practices "weaken the rule of law," he said. "Killings may be lawful in an armed conflict [such as Afghanistan], but many targeted killings take place far from areas where it's recognized as being an armed conflict."
John O. Brennan, Obama's top counterterrorism adviser, said April 30 U.S. drone attacks, wherever they take place, "prevent terrorist attacks on the United States and to save American lives."
He defended the strikes as "legal, ethical, and wise" and told the Woodrow Wilson International Center for Scholars in Washington, "We only authorize a strike if we have a high degree of confidence that innocent civilians will not be injured or killed, except in the rarest of circumstances."
Heyns told the Geneva conference of reports of "secondary drone strikes on rescuers who are helping [people injured] after an initial drone attack."
He said that if those reports prove true, "those further attacks are a war crime," the British newspaper The Guardian reported.
The United States did not sign the mandate for the International Criminal Court -- a 10-year-old permanent tribunal to prosecute individuals for genocide, crimes against humanity, war crimes -- where legal action could be started.
Heyns disparaged a U.S. suggestion that predator drone strikes on al-Qaida or allied groups were a legitimate response to the Sept. 11, 2001, terrorist attacks.
"It's difficult to see how any killings carried out in 2012 can be justified as in response to [the attacks] in 2001," he said.
U.S. officials said June 5 a drone strike in northwest Pakistan killed al-Qaida's second-in-command, Abu Yahya al-Libi, in the most significant U.S. victory against the militant Islamist organization since the May 2011 death of Osama bin Laden.
The officials said Libi was the only person killed in the attack. A tribesman from the area told the Times three to five other militants had been killed but no civilians had died.
Zamir Akram, Pakistan's ambassador to the U.N. office in Geneva, told the conference his country found "the use of drones to be totally counterproductive, in terms of succeeding in the war against terror."
"It leads to greater levels of terror rather than reducing them," he said.
Pakistan's Parliament passed a resolution in April demanding the drone campaign be stopped immediately.
The Obama administration responded to a report Heyns submitted to the Human Rights Council, saying in a statement there was "unequivocal U.S. commitment to conducting such operations with extraordinary care and in accordance with all applicable law, including the law of war."
The statement said the administration had a "continuing commitment to greater transparency and a sincere effort to address some of the important questions that have been raised."