Brian Finucane, a former State Department lawyer who is a specialist in counterterrorism issues and the laws of war, said that given the evidence that has emerged, the government’s statements, and after discussions with other national security lawyers in the week since the strike, he has formed stronger conclusions about the legality of the attack.

“I’m much more inclined to think this was just flat-out murder. And I’ve bent over backwards to be generous to the government in my interpretations,” he told The Intercept. “There are circumstances in which the U.S. can use lethal force but that is in the context of an armed conflict, against a lawful target — an enemy combatant. The Trump administration has not even bothered to make that argument. They have not argued that the United States is in an armed conflict governed by the law of war. They have not argued, much less substantiated, that the target of this attack was a lawful target.”