Definitions of Life and Death
A killing cannot be considered a criminal homicide unless the victim is a living human being. It is therefore important to define what constitutes life and what constitutes death. The question of what constitutes life generally comes up only in situations where a fetus is killed. The common law rule is that a fetus is not considered a living human being until it has been born alive. Therefore, if a defendant kills a pregnant woman he can only be charged with one count of murder for killing the mother, but no charges can be brought against him for the death of the fetus. Some jurisdictions have moved away from the common law rule and have ruled that a fetus is considered a living human being if, at the time it was killed, it would have been viable outside of the mother’s womb. Thus, if a defendant kills a pregnant woman and the woman is far enough along in her pregnancy so that the fetus could have lived outside of her at the moment the mother was killed, the defendant will be charged with two counts of murder, one for the mother and one for the fetus. If, however, the fetus could not have survived outside of the mother at the time the mother was killed, the defendant can be charged with one count of murder for the mother but cannot be charged at all for the death of the fetus. Some jurisdictions have moved even farther than that and have defined murder as the unlawful killing of a human being or fetus with malice aforethought.
As for the question of when death occurs, the traditional rule was that death occurred when the victim’s heartbeat and respiratory functions stopped. See Thomas v. Anderson, 96 Cal. App. 2D 371 (1950). However, more modern statutes have defined death as being the cessation of brain function. See State v. Fierro, 603 P.2d 74 (Ariz. 1979).