Sexual Abuse: A Journal of Research and Treatment, Vol. 17, No. 1, January 2005 (
Biological Fathers and Stepfathers Who Molest
Their Daughters: Psychological, Phallometric,
and Criminal Features
David M. Greenberg,
Kevin L. Nunes,
John M. Bradford,
and Susan Curry
A sample (N = 143) of men who sexually abused their biological daughters
or their step/adopted daughters were examined on a comprehensive array of
demographic and historical information, offense characteristics, psychological
and phallometric measures, and recidivism. Biological fathers were signiﬁcantly
less sexually aroused by children than were the stepfathers. On all the remaining
variables, however, no statistically signiﬁcant differences were found. Overall,
biological and stepfathers in the present study appear to be much more similar
than different from one another.
KEY WORDS: incest; sex offenders; child molesters; recidivism; phallometry; psychometric testing.
A valid distinction between incest perpetrators who are genetically related
biological fathers versus nonconsanguineous stepfathers may have bearing on pos-
sible etiologies and developmental mechanisms (Greenberg, Firestone, Bradford,
& Curry, 2000; Haig, 1999; Rice & Harris, 2002; Sagarin, 1977; Seto, Lalumi
& Kuban, 1999). For example, from an evolutionary perspective, compared to
men who sexually abuse their stepdaughters, men who sexually abuse their bio-
logical daughters are working against the interests of their inclusive genetic ﬁtness
(Haig, 1999). Whereas a man who sexually abuses his biological daughter likely
reduces the probability and extent to which his genes will be carried on into future
generations, a man who sexually abuses a girl who is unrelated to him, as in the
Department of Psychiatry, University of New South Whales and Western Australia, Australia.
School of Psychology, University of Ottawa.
Sexual Behaviours Clinic and Forensic Service, Royal Ottawa Hospital.
To whom correspondence should be addressed at School of Psychology, University of Ottawa, 120
University Private, Ottawa, Ontario, Canada K1N 6N5; e-mail: ﬁreston@uottawa.ca.
2005 Springer Science+Business Media, Inc.