The frustration-aggression theory says that violence is an unfulfilled need that leads to frustration, and the frustration is vented in aggression. If violence is acquired through the process of socialization, then aggressive or violent actions are most likely to occur in a culture or subculture in which violence is accepted or encouraged. Rational-choice theory looks at all forms of human behavior or evidence of the actor s conscious or unconscious weighing of costs versus benefits. Strategic crimes are defined as extortion, kidnapping, and blackmail. These crimes are called this because the violent act is one move in a complex game played by the criminal, the victim, and law enforcement agencies.
Murder is defined as the unlawful killing of a human being with malice aforethought.
Manslaughter is unlawful homicide without malice aforethought. Most murders occur during a quarrel between two people who know each other well. Many homicides are alcohol-related. The mentally ill commit murder at the same rate as the general population and serial killers are almost always psychotic. Assault is a threat or attempt to injure.