All that said, it is well known that police may not use excessive force. It is obvious, and was in real time, that Chauvin’s use of force on Floyd was excessive. And this was not a situation in which, after excessive force, everyone dusted off and went on their way. Mr. Floyd died.

Investigators did not need to be sure that they could make a third-degree murder charge stick to know that some kind of prosecutable homicide happened in the killing of George Floyd. This was not a fleeting incident, or a situation in which Floyd was resisting — he was pleading for his life. At the very least, this was a negligent homicide; more likely, it was something worse. Obviously, it was a crime. When a violent crime has clearly happened, the person who committed it should be placed under arrest, immediately.

I doubt it will be fatal to the case, but the prosecution is going to take some hits over the delay. Chauvin’s lawyers will contend that he was not arrested because investigators recognized that there was insufficient evidence; they will add that he was only charged because Minneapolis was burning and the mob had to be satisfied. I do not believe that claim will overcome the evidence of guilt. But the claim would not be available if Chauvin had been arrested promptly, as he should have been.