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The Concentration of Sex Offenses in British and Dutch Families

It is well established in criminological research, that a small group of offenders is responsible for a large share of total crime (Fox & Tracy, 1988; Piquero, 2000). This offending pattern does not only appear within cohorts of individuals but in cohorts of families as well. Previous research shows that criminal behavior in general (Farrington, Barnes, & Lambert, 1996; Farrington, Jolliffe, Loeber, Stouthamer‐ Loeber, & Kalb, 2001), and violent crime in particular (Van de Weijer, Bijleveld, & Blokland, 2014), is highly concentrated within families. Little is known about the concentration of sexual offending within families, as, to our knowledge, no study has focused on this topic before. In this chapter we will use prospectively collected data on the male family members in 397 British nuclear families and 140 Dutch extended families to examine the concentration of sexual offending in families, as well as possible explanations for such a concentration. We will also examine whether the degree of concentration differs for different types of sex offenses. In addition to the research indicating a concentration of crime within families, there is also empirical evidence of intergenerational transmission of crime, from father to son (e.g., Besemer, 2012; Bijleveld, & Wijkman, 2009; Van de Weijer et al. 2014), and intragenerational transmission of crime, between siblings (Farrington et al., 1996; Van de Rakt, Nieuwbeerta, & Apel, 2009). This inter‐, and intragenerational transmission of crime implies a concentration of crime within families, as multiple criminal family members are necessary for the transmission to occur. Studies that examined the intergenerational transmission of sex offenses have focused on the transmission of victimization rather than on the transmission of sexual offending The Concentration of Sex Offenses in British and Dutch Families 14