Recent controversial cases of killings by police have generated competing Black Lives Matter and Blue Lives Matter movements. Blue Lives Matter proponents claim that the focus on and protests in light of police killings of unarmed black persons is unwarranted. Part of this dispute turns on the moral evaluation of the killing of citizens by law enforcement. To address the dispute, I develop an account of the special moral obligations of law enforcement and show how it can be applied. I (...) argue that members of law enforcement have special moral obligations against killing citizens. The account generates moral guidance for law enforcement in a number of other ways. It implies, finally, that the Blue Lives Matter proponents fundamentally misunderstand the ethics of law enforcement. (shrink)