The killing of Tyre Nichols by five Memphis police officers arose from what has become a flashpoint of race and brutality: the police stop of a vehicle. The videos released last week depict yet another shocking episode of a traffic stop turning into a lethal attack on a Black motorist. Police officers were the ones seen delivering the blows, but make no mistake, responsibility for attacks like the one on Mr. Nichols lays with many, including the courts.