Typologies of sexual offending of federally-sentenced women: a validation study

Research Highlights: Women sex offenders can be classified into four typologies with distinct offending characteristics, pathways, and needs.

Although the number of women who commit sexual offences is small, it is important to understand the motivations and factors underlying their sexual offending to facilitate the development of correctional programming and enhance reintegration efforts.

The current study was conducted to assess the validity of the Descriptive Model of Female Sexual Offending (DMFSO; Gannon, Rose, & Ward, 2008, 2010, 2012) used to classify women sex offenders into one of three typologies. Additionally, the current study assessed the validity of an additional typology (fourth) proposed by Lutfy and Derkzen (2014).

The DMFSO is a women-specific offence process model that considers the role of cognitive, behavioural, affective, and contextual factors that lead up to a Women Sex Offender’s (WSO’s) index offence. It also takes into account the offenders’ background factors as well as the pre-offence, offence, and post-offence periods. Based on these factors, it proposes three distinct typologies for WSOs: Explicit-Approach, Directed-Avoidant, and Implicit-Disorganized. In previous research the DMFSO had been found to be a reliable way to classify WSOs incarcerated in the Canadian federal correctional system (Lutfy & Derkzen, 2014); nevertheless, this research recommended an additional fourth pathway referred to as the Adopted-Approach.

Thirty-three women convicted of sexual offences who had participated in the women sex offender program (WSOP) between the years 2010 and 2017 were randomly selected to be included in the study. File information from criminal profiles, correctional plans, and psychological reports were coded independently by two researchers using the modified DMFSO Preliminary Offence Pathway Checklist (Gannon, Rose, & Ward, 2012; Lutfy & Derkzen, 2014).

Just over 90% of the sample was classified into one of the four distinct pathways. Interrater reliability was conducted on about 50% of files with a classification agreement of 87.5%. However, low numbers made it difficult to establish a reliable level of interrater agreement on Implicit-Disorganized typology. The additional fourth typology proposed by Lufty and Derkzen was also found in this sample and therefore appears to measure a unique WSO offending pattern. In total, the largest proportion of WSOs fell within the Explicit-Approach typology, followed by the Directed-Avoidant and Adopted-Approach. These results were consistent with those of Lutfy and Derkzen (2014) who reported similar proportions of WSOs within each typology.

Findings suggest that file review instead of interviews could be used to apply the modified DMFSO (Gannon et al., 2010, 2012; Lutfy & Derkzen, 2014) to classify federally-sentenced WSOs to one of four distinct typologies. The largest single typology (over one-third of the women) offended for reasons of self-gratification and were not unduly influenced by a male co-accused.

Future research would benefit from using a larger sample of WSOs to examine the utility of the DMFSO and the additional fourth typology proposed by Lutfy and Derkzen for classifying WSOs and examining the recidivism rates within each typology would also aid with treatment efforts and risk assessment.

Wanamaker, K. A., Derkzen, D., & De Moor, C. (2018). A Validation of Four Pathways to Women Who Sexually Offend (Research Report R-417). Ottawa, Ontario: Correctional Service of Canada.

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