Airstrikes by the United States on alleged drug-smuggling boats, which have killed more than 220 people, violate international law and plausibly constitute crimes against humanity, a United Nations legal expert said in a paper published on Monday.
Ben Saul, the U.N. special rapporteur monitoring human rights in the context of counterterrorism, also challenged the legality of the U.S. seizure of Nicolás Maduro, then the president of Venezuela, and aspects of U.S. collaboration with Latin American states under the Trump administration’s “Shield of the Americas” initiative.
Mr. Saul focused particularly on 68 military strikes carried out by the U.S. military on what it said were drug-carrying vessels in the Caribbean and Pacific between September 2025 and August 2026, killing at least 223 people.
The attacks have been part of a military offensive designated “Southern Spear” launched in September 2025 with the stated aim of interdicting drug smuggling by organizations linked to drug cartels. The United States has not offered evidence that the boats carried drugs, but even if they were, experts have questioned the legality of the attacks.
“There are reasonable grounds to believe that the reported 68 attacks that killed 223 people constituted crimes against humanity of murder under customary international law,” Mr. Saul, a professor of international law at Australia’s University of Sydney, concluded.
The Pentagon had no immediate response to Mr. Saul’s report.
This month, which was not covered by his report, the Pentagon has announced two more strikes, including one on Saturday, raising the total to 70 vessels and 234 people killed.
Even if the crews of the boats were members of criminal groups that the Trump administration has designated as terrorist organizations, they had not mounted any armed attack on the United States that would give it the right of self-defense, Mr. Saul wrote. “Drug trafficking is not equivalent to a military attack,” he wrote.
Moreover, the airstrikes on these vessels could not be considered as a necessary or proportionate response given the availability of other means to intercept them, he added.
Mr. Saul’s paper adds to the growing critiques from lawyers and human rights experts of the Trump administration, which withdrew the United States from the U.N. Human Rights Council and says it gives no weight to the council’s statements. A U.N. fact-finding mission that last week found U.S. airstrikes on Iran may have amounted to war crimes took note of public statements by American officials, including Mr. Trump and Defense Secretary Pete Hegseth, that it said were dismissive of U.S. obligations under international law.
U.N. human rights chief Volker Türk last year condemned the attacks on alleged drug trafficking vessels as a violation of international law, and called for investigation and, possibly, prosecution of those responsible. Mr. Saul also raised the question of possible criminal liability for those responsible for issuing or carrying out illegal orders.
But Mr. Saul’s paper went farther in challenging the legal basis for much of the wider U.S. strategy pursued by the Trump administration to combat narco-terrorism in the region, including the U.S. military’s seizure of Mr. Maduro in January. He was charged with involvement in large-scale drug trafficking.
The seizure of Mr. Maduro, in which at least 75 people were killed, constituted a prohibited use of force, Mr. Saul wrote.
U.S. efforts to expand multilateral and bilateral cooperation in the fight against narcotics trafficking, under the Shield of the Americas initiative promoted “a highly securitized response without explicit commitments to human rights and international law, or to addressing root causes of organized crime such as poverty, corruption and State weakness,” he wrote.
Mr. Saul concluded his paper with a stinging critique of the ineffectiveness of the U.S. strategy. The Drug Enforcement Administration had concluded that the military action had not reduced the supply, price or purity of cocaine in the United States, he noted. Much of the cocaine arrives in container ships that are not routinely inspected, not the small boats targeted in airstrikes.
Military attacks have focused on cocaine smuggling and not on the fentanyl and opioids responsible for most U.S. drug-overdose deaths and not for the most part transported by sea from Venezuela, he added.