OBJECTIVE: This study examines the role of elevated autonomic nervous system reactivity in protecting individuals at high risk for criminal behavior from antisocial outcomes. The authors hypothesized that subjects with criminal fathers who did not become criminals themselves were biologically protected from such an outcome because of, in part, heightened responsiveness of the autonomic nervous system. METHOD: Ninety-four male subjects were placed into one of four study groups: criminal with criminal father (N = 26), noncriminal with criminal father (N = 24), criminal with noncriminal father (N = 20), and noncriminal with noncriminal father (N = 24). Skin conductance and heart rate data were gathered in an orienting paradigm. RESULTS: Skin conductance and heart rate orienting reactivity were found to be significantly higher in the group of noncriminal subjects with criminal fathers than in the other three groups. CONCLUSIONS: For subjects at high risk for criminal behavior, heightened autonomic nervous system responsiveness appears to be associated with lower likelihood of criminal outcome.Abstract Teaser