Testing the Behavioural and Environmental Consistency of Serial Sex Offenders: A Signature Approach

Abstract

The present study examines consistency of crime behaviour among 347 sexual assaults committed by 69 serial sex offenders. This individual behaviour approach—the so‐called signature approach—reveals which features of crime behaviour are consistent across a series and which features are not. The consistency scores were calculated using the Jaccard's coefficient. The results of this study indicate that there are some crime features of a serial sexual assault that can be useful for the purpose of linkage. Another important finding is that consistency scores for different variables within the same category can differ substantially. Moreover, serial sex offenders are more likely to be consistent in their environmental crime features when they are also consistent in their behavioural features, and vice versa. Serial sex offenders are also more likely to be consistent in the behavioural features of their assaults as the crime series gets longer. The implications of the results are discussed in relation to both research and practise. Copyright © 2012 John Wiley & Sons, Ltd.

Behavioral Consistency Among Serial Burglars

“…It therefore remains unclear whether offenders become more consistent in behavior as they learn their strengths and gain expertise, as the personality psychology literature suggests (Caspi & Bem, 1990;Mischel, 1999), or if offenders change their behavior depending on what they learn in the field and adapt easily to environments suitable for different styles of offenses once they become more prolific in their criminal career (Blumstein et al, 1988;Harbers et al, 2012;Sorochinski & Salfati, 2010). The J coefficient suggests an inverse and potentially non-linear relationship between the number of crimes committed and offending style consistency, while the D Index suggests that offenders may become increasingly and significantly more consistent as they commit more crimes.…”

Same-sex child molestation within the Boy Scouts of America initiation and termination in victim narratives.

“…Based upon crime script analyses on different victim activities prior to crime, Deslauriers-Varin and Beauregard (2010) suggested increasing the level of guardianship might help reduce the risk of sexual victimization especially in the outdoor scripts. This finding is congruent with the finding of Harbers et al, (2012) in analyzing offenders' preference for isolated locations to carry out their crime. Public settings often offer the greatest potential for control over the environment as authorities can design or reconstruct these public places accordingly.…”

“…This finding suggests that even though such surroundings served as good supplies of potential victims, those locations presented potentially more unforeseen situational factors (e.g., witnesses) that could interfere with the crime (Harbers et al, 2012). The risks of sexual victimization decreased when victims were more involved in activities with strangers or casual acquaintances, and when greater proportions of time were spent alone by victims (Mustaine & Tewksbury, 2000), which is consistent with the previous findings on the danger of vocational child molesters that they are vested in being alone with children, and the amount of time spent together was associated with the increasing risk of victimization.…”

“…A study of 69 serial sex offenders and their crime locations revealed that the use of residential areas for the encounter and the crime appeared to be relatively consistent while the use of commercial areas were not (Harbers et al, 2012). This finding suggests that even though such surroundings served as good supplies of potential victims, those locations presented potentially more unforeseen situational factors (e.g., witnesses) that could interfere with the crime (Harbers et al, 2012).…”

“…A study found that an offender with a male victim was more likely to be consistent in the victim's gender (Harbers et al, 2012). However, when the victim was a male child in an older age group, the offender was more likely to use manipulation/persuasion techniques to foster his victim's participation in the course of sexual abuse (Leclerc et al, 2009).…”