| Abstract: | Attention is called to several recently advanced lines of evidence underscoring the role of contagion in antisocial behavior. One line of evidence consists of findings that the onset of antisocial behavior in one sibling increases the risk to other siblings. A second line of evidence shows that the tendency of monozygotic twins to be more concordant for antisocial behavior than dizygotic twins can be explained by contagion as well as heredity. In addition, there are differences in prevalence between same-sexed and opposite-sexed twins that contagion can explain, but heredity cannot, at least not without numerous ad hoc auxiliary suppositions. Third, behavioral contagion is also able to explain, and very precisely, the temporal course of aggregate delinquency through adolescence. Fourth, evidence has been presented that antisocial behavior is an equilibrial phenomenon, that is, that it depends on a balance between antisocial and prosocial forces, a balance (or imbalance) that would explain the sudden leaps and falls that crime statistics sometimes take. Finally, programs to combat drug use are often modestly successful and almost all such programs presuppose that drug use is contagious. The paper closes with two sections on the implications of these findings, first for theory and research and then for policy and practice. |
