"In this compelling book, Lawrence M. Friedman looks at situations where killing is condemned by law but not by social norms and, therefore, is rarely punished. He shows how penal codes categorize homicides by degree of intent, which are in turn based on society's sense of moral outrage. Despite being officially defined as murder, many homicides have historically gone unpunished. Friedman looks at early vigilante justice, crimes of passion, murder of necessity, mercy killings, and assisted suicides. In his explorations of these unpunished homicides, Friedman probes what these circumstances tell us about conflicts in social and cultural norms and the interaction of law and society"--"Murder is the king of crimes. No crime is worse, except (perhaps) treason. Murder is defined, basically, as the unlawful killing of another human being; but every society has its own understanding of which killings are lawful, and which are not.

Only law and custom can tell us exactly what "murder" means in a given legal order. A justified or excusable killing is not murder. For example, in California, a killing is "excusable" if it was "committed by accident or misfortune;" and is "justifiable" when done in self- defense (or in the "lawful defense" of a member of the family). You can kill someone who, for no good reason, is about to plunge a dagger into your heart. In wartime, during battle, soldiers have a positive duty to kill the enemy. But soldiers are not supposed to kill prisoners of war; or enemy soldiers who surrender"--.