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Overnight, protests of the egregious police killing of George Floyd roiled several American cities, including Minneapolis, where riots and looting frightened locals and destroyed livelihoods.

A prudent president would have urged calm.

On Twitter, President Donald Trump instead aggressively insulted elected officials in Minneapolis. “A total lack of leadership,” he wrote. “Either the very weak Radical Left Mayor, Jacob Frey, get his act together and bring the City under control, or I will send in the National Guard & get the job done right.”

Then Trump threatened to unleash American carnage on looters. “These THUGS are dishonoring the memory of George Floyd, and I won’t let that happen,” he declared in a second tweet. “Just spoke to Governor Tim Walz and told him that the Military is with him all the way. Any difficulty and we will assume control but, when the looting starts, the shooting starts.”

Twitter quickly appended a note to the president’s message: “This Tweet violated the Twitter Rules about glorifying violence,” it stated. “However, Twitter has determined that it may be in the public’s interest for the Tweet to remain accessible.” It isn’t clear that threatening to shoot looters technically glorifies violence, but the ostensible Twitter violation, which quickly made headlines, is less important than the constitutional problem with Trump’s public threat of lethal force.

As the legal scholar Orin Kerr noted, “Actually following a policy of ‘when the looting starts, the shooting starts’ would violate the 4th Amendment, for starters.” He cited the precedent in Tennessee v. Garner.

That case originated in Memphis, where two police officers, including Elton Hymon, were dispatched to catch a prowler. In the backyard of a house, Hymon saw a suspect he judged to be 17 or 18 run to a back fence. “Halt,” he said, “police.” The suspect tried to climb over the fence to escape. Hymon shot him in the back of the head and recovered a purse with $10 in it. He later cited a Tennessee statute that said, “If, after notice of the intention to arrest the defendant, he either flee or forcibly resist, the officer may use all the necessary means to effect the arrest.”

The Supreme Court’s holding in the 1985 case sets forth a different standard:

The use of deadly force to prevent the escape of all felony suspects, whatever the circumstances, is constitutionally unreasonable. It is not better that all felony suspects die than that they escape. Where the suspect poses no immediate threat to the officer and no threat to others, the harm resulting from failing to apprehend him does not justify the use of deadly force to do so. It is no doubt unfortunate when a suspect who is in sight escapes, but the fact that the police arrive a little late or are a little slower afoot does not always justify killing the suspect. A police officer may not seize an unarmed, non-dangerous suspect by shooting him dead. The Tennessee statute is unconstitutional insofar as it authorizes the use of deadly force against such fleeing suspects.

That is the law of the land.

The decision goes on to note that:

where the officer has probable cause to believe that the suspect poses a threat of serious physical harm, either to the officer or to others, it is not constitutionally unreasonable to prevent escape by using deadly force. Thus, if the suspect threatens the officer with a weapon or there is probable cause to believe that he has committed a crime involving the infliction or threatened infliction of serious physical harm, deadly force may be used if necessary to prevent escape, and if, where feasible, some warning has been given.

More succinctly: Cops can’t just shoot someone looting gadgets from a Target or whiskey from a liquor store.

Trump swore to protect and defend the Constitution. He just violated that oath. When he wrote “when the looting starts, the shooting starts,” he implicitly urged law enforcement to adopt an approach that would transgress the Constitution, violate Fourth Amendment rights, and cause unlawful deaths. Rioting is abhorrent. Trump’s incendiary call for illegal acts is more likely to fuel than stop it––especially if any police act on his irresponsible words.

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