Are There Early Risk Markers for Pedophilia? A Nationwide Case-Control Study of Child Sexual Exploitation Material Offenders

Abstract

Although prior research suggests associations between parental characteristics and later sexual offending in offspring, possible links between early pregnancy-related factors and sexual offending remain unclear. Early risk markers unique to sexual offending, however, may be more prominent among sexual offenders with atypical sexual interests, such as individuals involved with child sexual exploitation material (CSEM; also referred to as child pornography). We examined the prospective association between parental and pregnancy-related risk markers and a behavioral indicator of pedophilic interest, CSEM offending. All 655 men born in Sweden and convicted of CSEM offending between 1988 to 2009 were matched 1:5 on sex, birth year, and county of birth in Sweden to 3,928 controls without sexual or nonsexual violent convictions. Paternal age (adjusted odds ratio [AOR] = 1.3, 95% confidence interval [CI] [1.1, 1.7]), parental education (AOR = 0.8, 95% CI [0.6, 0.9]), parental violent criminality (AOR = 2.9, 95% CI [2.2, 3.8]), number of older brothers (AOR = 0.8, 95% CI [0.6, 0.9] per brother), and congenital malformations (AOR = 1.7, 95% CI [1.2, 2.4]) all independently predicted CSEM convictions. This large-scale, nationwide study suggests parental risk markers for CSEM offending. We did not, however, find convincing evidence for pregnancy-related risk markers, with the exception of congenital malformations and having fewer older brothers.

Acknowledgments

We would like to thank Christina Norrby for help in defining and obtaining the registry data sets. Funding was provided in part by the Swedish Research Council: Medicine (Dr. Långström); the Canadian Institute for Health Research (CIHR Banting fellowship; Babchishin); The Royal's Integrated Forensic Program (Postdoctoral Fellowship; Babchishin) and the Wellcome Trust (202836/Z/16/Z; Fazel).

Notes

¹ We conducted a sensitivity analysis by removing all offenders who were under 19 years of age (n = 112) and their matched controls. There was no appreciable effect on the findings. See Online Supplemental Materials for tables.

² The effect of older brothers may be confounded by family size. Hence, we examined a multivariate model that controlled for total number of siblings. The number of older brothers continued to predict CSEM offenses even after controlling for total number of siblings (older brother AOR = 0.81, 95% CI [.68, .97]; total siblings AOR = .84, 95% CI = [.76, .93]). We also computed the older brothers ratio (number of older brothers/total number of other siblings; Barbaree, 2018, with larger ratios reflecting a greater number of older brothers relative to other sibling types) as an alternative way to control for sibling number. We found a mean ratio of .15 (SD = .38) for the CSEM group and .23 (SD = .50) for control group; this ratio had a similar association with CSEM offending (older brothers ratio OR = 0.67, 95% CI [0.51, 0.90]) as the raw total number of older brothers. In short, the effect of older brothers remains relevant even after controlling for other siblings.