Arguably, one of the most substantial contributions to empirical exploration of the mechanisms of peer influence has been research on deviancy training, an interactional process characterized by repeated peer reinforcement for talk about antisocial acts and attitudes (e.g., Dishion, Spracklen, Andrews, & Patterson, 1996; Granic & Dishion, 2003). Through careful observation of friendship dyads engaged in conversations, this research has demonstrated that peer reinforcement of antisocial behavior occurs through positive affective behaviors, such as smiling and laughing, in response to deviant talk. Among adolescent males at risk of antisocial outcomes, research before this decade had shown that this process is associated with increases in antisocial and health-risk behaviors, such as substance use and violence (e.g., Dishion et al., 1996). Ample work from the past 10 years has continued to examine this process as a key mechanism of contagion for antisocial or deviant behavior across gender and development. For instance, this work has suggested that deviancy training occurs in female adolescents, although to a lesser degree than among male adolescent dyads (Dishion, 2000; Piehler & Dishion, 2007). The process also has
