Biopsychosocial criminological theories suggest that it is important to consider interactions between risk factors from different domains in the prediction of externalizing behavior. Lower resting heart rate is considered the best replicated biological risk factor for externalizing behavior. The psychological construct of empathy has also shown to be predictive of such behavior, but little is known about the potential interaction between these two different risk factors in predicting externalizing behavior. We examined the moderating role of empathy on the association between resting heart rate in childhood and adolescence with externalizing behavior by young adulthood using two subsets of participants from the Longitudinal Risk Factors for Antisocial Behavior project: Subsample 1 (n = 697) at ages 9–10 and 19–20 years and Subsample 2 (n = 394) at ages 14–15 and 19–20 years. Linear and logistic regressions showed that empathy moderated the association between resting heart rate in adolescence and externalizing behavior by young adulthood. Among individuals with low but not high levels of empathy, increased resting heart rate predicted lower levels of externalizing behavior. Interventions enhancing empathic skills in individuals with psychophysiological risk profiles could be beneficial.
