Alone among citizens, police have the right to use deadly force to compel compliance and obedience. As a society, we give them broad discretion to do so, judging them on a standard of “objective reasonableness,” where an officer’s use of force “must be judged from the perspective of a reasonable officer on the scene.” If an officer believes someone could imminently cause serious injury or death—or if he fears for own his life—he can shoot.