One of the most consistent findings in aggression and criminology research is that aggression is a relatively “stable,” self-perpetuating behavior that begins early in life [Farrington, 1989, 1995; Huesmann and Moise, 1998; Huesmann et al., 1984, 2002; Juon et al., 2006; Kokko et al., in press; Loeber and Dishion, 1983; Moffitt et al., 2001; Olweus, 1979; Tremblay, 2000; Zumkley, 1992]. In this case, stability refers to “continuity of position” within the population: the more aggressive child grows up to be the more aggressive adult. Some researchers [Loeber, 1982; Moffitt, 1990] have argued that the continuity in aggression found in many past studies is because of only a few highly aggressive people. According to Moffitt’s [1993] developmental taxonomy, there are two types of aggressive people: those for whom aggression or antisocial behavior is stable and persistent (Life-Course-Persistent) and those for whom it is temporary and situational (Adolescent-Limited). Moffitt argues that only a very small percentage of aggressive or antisocial adolescents have the more stable, persistent form and that it is this small group that is driving the statistical continuity found in studies of aggression and antisocial behavior.
