Doctoral Researcher Teresa da Silva has had her paper examining heterogeneity within multiple perpetrator rapes accepted for publication by Sexual Abuse: A Journal of Research and Treatment. “Heterogeneity within Multiple Perpetrator Rapes: A National Comparison of Lone, Duo and 3+ Perpetrator Rapes” was written by Teresa da Silva and her supervisors Dr Jessica Woodhams and Dr Leigh Harkins. Although this type of sexual violence has received much attention in international news recently, it is an under-researched area. With the exception of one published study by Amir (1971) which is now more than 40 years old, the effect of the number of perpetrators involved in multiple perpetrator rapes (MPR) on offence characteristics has not been considered by most researchers in the area. This is despite the fact that the theoretical literature from social psychology suggests that there are differences in the way duos and larger groups interact.

Teresa da Silva

The paper reports on the first current study of its kind investigating the offence, offender and victim characteristics of rapes committed by lone perpetrators, duos and groups of 3+ offenders. A national sample of 336 allegations of completed and attempted rape of female victims from the United Kingdom was analyzed. Rapes committed by multiple (duos and groups of 3+ perpetrators) and lone offenders were compared on offence characteristics (incorporating the approach, maintenance and closure phases of each rape) and victim and offender socio-demographic characteristics. Significant differences between rapes committed by lone, duo and 3+ group offenders were found in the age and ethnicity of the offenders; the type of approach used; the locations of the initial contact, assault and release of the victims; the use of a vehicle; the precautions utilized; the verbal themes present; and the sex acts performed. These results have implications for educational prevention programs, interventions with offenders and for rape victim support.

Following on from this study, Teresa da Silva has conducted interviews with convicted MPR offenders to more clearly identify whether lone, duo or 3+ group perpetrators differ in their motivations. The information provided by the offenders contributes to the understanding of what pre-empted the offence and decision-making.

da Silva, T., Woodhams, J., Harkins, L. (in press). Heterogeneity within Multiple Perpetrator Rapes: A National Comparison of Lone, Duo and 3+ Perpetrator Rapes. Sexual Abuse: A Journal of Research and Treatment