Former Minneapolis police officer Derek Chauvin has been convicted of murder for killing George Floyd—a verdict that most Americans will likely find just. But of course, that conviction will not bring Mr. Floyd back to life, nor should we suppose that the criminal justice system reliably punishes officers who violate people’s rights. To ensure proper accountability we must eliminate the judge-made doctrine of qualified immunity, which too often prevents civil-rights plaintiffs from holding police and other government officials liable for the harms they commit under color of law.