The life histories and psychological profiles of 59 incestuous stepfathers.

Incest is both more common and more severe in stepparent families. The reasons for this have been unclear. In this comparison of 59 incestuous stepfathers, 70 incestuous biological fathers, and 158 offenders against unrelated children, there were few substantial differences in psychological characteristics between fathers and stepfathers, but their life histories and marital histories differed significantly. Stepfathers were significantly more likely to have prior convictions for sexual offenses, to have been sexually abused as a child, and to have juvenile criminal records. Stepfathers were more likely to have histories of previous marital failure. There was great heterogeneity of psychological characteristics. Increased prevalence in incest in stepfamilies is probably related to interactions between stepfathers' psychopathology, problems inherent in stepfamilies, and the availability of a potential victim.