Can the offence behaviours of stranger rapists discriminate between UK and non-UK nationals

Abstract

Currently, no research is available for behavioural investigative advisors’ to provide justifications to infer from the crime scene that an offender is a UK or non-UK national. The paper aims to discuss these issues. Data were obtained from National Crime Agency and consisted of 651 stranger rapes, 434 UK nationals and 217 non-UK nationals. All cases were coded for 70 offence behaviour variables. χ² analyses were conducted to identify significant associations between offence behaviours and offender nationality. Significant associations were then entered into a logistic regression analysis to assess their combined predictive ability of offender nationality. Analyses revealed 11 offence behaviours with significant associations to offender nationality: confidence, darkness, offender kisses victim, victim performs sex acts, requests sex acts, apologises, destroys forensics, block entry/exit, weapon – firearm, vaginal penetration – hands/fist/digital, and violence: minimal. From this, seven variables held predictive ability within the logistic regression, with five predicting the non-UK grouping and two the UK grouping. Future research should test the distinctions between UK and non-UK national stranger rapists and explore the impact of length of residency. Results indicated that on the whole UK and non-UK stranger rapists display similar behaviours, but there were some distinct behaviours within stranger rape crime scenes, particularly the use of firearms. The ability to use crime scene behaviours to narrow suspect pools by criminal conviction is only useful when police have access to full criminal histories. Unfortunately, the ability to access and search non-UK databases is not always possible. Therefore, this study may be the first step for BIAs to utilise in identifying the likely offender nationality, before using further models that narrow down to criminal history. This is the first study to examine whether it is possible to differentiate stranger rapists nationality using their offence behaviours.