GENEVA — A United Nations expert investigating summary executions said on Thursday that the United States’ targeted killing of Maj. Gen. Qassim Suleimani of Iran was unlawful and risked eroding international laws that govern the conduct of hostilities.
Agnes Callamard, the United Nations special rapporteur investigating extrajudicial and summary executions, said that the American drone strike that killed General Suleimani as he arrived in the Iraqi capital, Baghdad, in January could only be justified in international law as a response to an imminent threat. The United States had provided no evidence to support that position, she said.
“Absent an actual imminent threat to life, the course of action taken by the U.S. was unlawful,” Ms. Callamard wrote in a report that she presented on Thursday to the U.N. Human Rights Council in Geneva.
The retaliatory missile attacks Iran launched against American bases in Iraq five days later were also “completely outside the scope of what is permissible” in international law, Ms. Callamard said.
Ms. Callamard’s report as a United Nations independent expert is intended as an international wake-up call that will help to generate critical scrutiny and action on issues hitherto debated mainly by academics, lawyers and security experts.
There is an urgent need for international action to monitor and regulate the use of drones and the threat they pose to international law, Ms. Callamard said. In the absence of a clear legal framework for holding states accountable for drone strikes, she called for the U.N. Security Council to review all targeted killings and for the U.N. High Commissioner for Human Rights to submit annual reports on drone strike casualties.
A State Department spokeswoman, Morgan Ortagus, condemned Ms. Callamard’s report as “dishonest” and “tendentious” and said that, by “giving a pass to terrorists,” it underscored why the United States was right to leave the Human Rights Council in 2018.
General Suleimani commanded Iran’s Islamic Revolutionary Guard Corps, a branch of the military that ran clandestine operations across the Middle East and was designated by President Trump as a foreign terrorist organization in April 2019.
President Trump and Secretary of State Mike Pompeo said they ordered the strike in response to an imminent threat of attack but provided no evidence in official explanations to Congress and the United Nations.
In a memo to Congress, the administration said only that it carried out the strike as a response to previous Iranian attacks and “to deter Iran from conducting or supporting further attacks against United States forces and interests.”
The information that Trump administration officials provided was “remarkably vague and inconsequential as far as a possible imminent threat is concerned,” Ms. Callamard wrote in the report. “Even at the most basic level, the U.S. did not demonstrate that striking Suleimani was ‘necessary.’”
Instead, she said, the United States strike on General Suleimani set an alarming precedent for the use of drones in targeted killings. Until January, such strikes had been limited to individuals in nonstate groups. Ms. Callamard said that the United States attack on General Suleimani was the first targeted drone killing of a senior foreign government official on the territory of a third country.
“It is hard to imagine that a similar strike against a Western military leader would not be considered as an act of war,” she wrote.
As a result of the killing, the international community faced “the very real prospect that states may opt to ‘strategically’ eliminate high ranking military officials outside the context of a ‘known’ war, and seek to justify the killing on the grounds of the target’s classification as a ‘terrorist’ who posed a potential future threat,” Ms. Callamard said in her report.
“If you have a few more countries moving in that direction, the real risks of global conflagration are becoming very high,” she told reporters in Geneva. “There are no red lines.”
Ms. Callamard presented her findings on the killing of General Suleimani as a case study illustrating the wider dangers posed by what she called the “extremely scary” unregulated growth in the use of armed drones and the dramatic escalation of their capabilities.
The armed forces of at least 102 countries now operated drones, she said, along with at least 20 nonstate actors, including the Islamic State and the Libyan militia led by General Khalifa Hifter. Around 40 states possessed or were procuring armed drones, and at least 11 countries had used drones for military strikes, including targeted killings.
Ms. Callamard also attacked the notion that armed drones enabled precise, surgical strikes as “a myth,” citing the heavy civilian casualties inflicted in the course of drone strikes in Afghanistan, Pakistan and Yemen, often as a result of faulty intelligence.
Ms. Callamard said that analysis of classified data on American drone strikes in Afghanistan from 2010 to 2011 found they were ten times more likely to cause civilian casualties than conventional air attacks. Data from Pakistan in 2015 indicated that missed strikes on 24 individuals had killed more than 870 other people.
Pranshu Verma contributed reporting from Washington.