Offender types and criminality dimensions in male juveniles convicted of sexual offenses.

Previous studies have described juveniles who sexually offended (JSO) as a rather heterogeneous population. In consequence, different typologies of JSO have been proposed for a better understanding of the causes and interventional needs of JSO. Three previously described types have received support in previous studies, namely, the victim age type (JSO offending against children vs. adolescents or adults), the co-offender status type (JSO offending as singles vs. in groups), and the crime history type (JSO with vs. without a previous history of crime). The validity of these types is tested in a consecutive sample of 223 criminal male adolescents, who had been convicted of a sexual offense between 2000 and 2008 in the Canton of Zurich (Switzerland). By analyzing nine offender characteristics, four victim characteristics and six offense characteristics, the best evidence is found for the victim age-based type. The co-offender status and the crime history types are less well supported. However, all three types are related to each other and do not provide a comprehensive characterization of JSO. Therefore, an additional principal component analyses is performed searching for basic dimensions of juvenile sexual delinquency and leading to the following factors: "single offender with severe molestation of a related child," "persistent general delinquent with migrant background," "older offender with alcohol use and familial constraints," "multiple and aggressive offender with social adversities," and "offender with unselected and multiple victims." These five dimensions reflect different relevant factors of sexual offending behavior in male juveniles and may have further impact on forensic and clinical practice.