Case linkage is a statistical technique which connects multiple sexual assault cases to a single perpetrator and holds promise for informing criminal investigations. Further, examining the behaviours executed most consistently across serial offences committed by a given offender is crucial to linking offences. The current study investigated behavioural consistency in a sample of 49 male serial stranger sexual offenders responsible for 147 offences. For each offence, four crime aspects were identified: 1) pre-crime facilitators, 2) victim selection and characteristics, 3) approach and attack methods, and 4) crime scene characteristics. Consistency between and within each crime series and across offender types based on background characteristics was examined. Results indicated a high degree of behavioural consistency across all crime aspects. Behaviours occurring prior to the offence were particularly useful in establishing consistent offending patterns. The implications of these findings in the context of police investigations and their utility for clinical practice are discussed.

Assessing and managing level of violence risk among forensic mental health patients is a primary role of clinical staff. Forensic risk assessments are typically focused on risk factors and deficits, whereas patient protective factors are either partially included or excluded by clinicians. The Structured Assessment of Protective Factors for Violence Risk (SAPROF) is a recently developed measure of protective factors designed to augment the conventional use of risk assessment tools with a correctional/forensic population. In the current study, the psychometric properties of the SAPROF were examined in a sample of 50 forensic inpatients and outpatients found Not Criminally Responsible (NCR) at a psychiatric hospital in Ontario, Canada. The SAPROF was found to have adequate internal, intrarater, and interrater reliability. Using a subsample of inpatients only, incremental predictive validity was demonstrated for institutional misconducts at six-month follow-up over the HCR-20 V3. Taken together, the results suggest that the SAPROF may be a useful addition to clinical practice and inform review board decisions about risk prediction, risk management, and treatment planning.

The present study investigated behavioural consistency across sexual offending. Variations in behavioural consistency may arise from an increased influence of situational and contextual aspects. However, there is paucity of research exploring variations in behavioural consistency relative to the temporal sequence of the behaviour (e.g., occurring prior to or during the offence). A sample of 49 male serial stranger sexual offenders responsible for 147 offences across four temporal phases of a sexual offence was used in the current study. For each offence, four crime phases were identified: 1) pre-crime, 2) victim selection, 3) approach, and 4) assault. Behavioural consistency within and across offence series were examined utilizing Jaccard's Coefficient and Receiver Operating Characteristics (ROC). Results indicated a high degree of behavioural consistency across all crime aspects; behaviours that were more dependent on situational influences were inherently less predictable and demonstrated to be less consistent. Further, increased behavioural consistency was associated with offender characteristics of a more stable nature. The implications of these findings are discussed.

The current study seeks to advance the faceted multidimensional scaling (termed FMDS) procedure used in much of the investigative psychology research. To this end, recent research on street robbery by Goodwill and colleagues will be utilised to illustrate the effectiveness of a facet scale method for offender profiling. Four FMDS themes of street robbery (Con, Blitz, Confrontation and Snatch) were revealed by the crossing of two underlying axial facets: the offenders' level of violence and interaction with the victim. The facet scale method, utilising offenders' axial facet scores, was compared to previous count, proportional and centroid classification methods in the prediction of offender criminal histories. Utilising logistic regression and receiver operating characteristic analyses, the axial facet scale method was found to significantly outperform the qualitatively based dominant theme classification methods that typically employ angular and radial facets for FMDS interpretation. Implications for the use of axial facet scales within FMDS analysis for offender profiling research are discussed. Copyright © 2012 John Wiley & Sons, Ltd.

In a recent study of personal robbery, commissioned by the Home Office in the UK, a qualitative typology of robbery offences was proposed based on the approach used by the offender to commit the crime, consisting of four approach types: Blitz, Confrontation, Con, and Snatch. Conceptual inspection of the typology reveals that these proposed types may be hypothetically demarcated as the product of two latent dimensions: interaction (between the offender and the victim) and violence (used to threaten/harm the victim). The current paper utilises crime scene information from 72 incarcerated male offenders convicted of ‘street’ robbery to test this hypothesis. Convergent statistical analysis was utilised to test the structure of Smith's typology first using multidimensional scaling (MDS) and then principal component analysis (PCA). MDS and PCA analyses provided convergent support for the existence of the four robbery styles and the latent dimensions of interaction and violence. Implications of Smith's typological structure and latent behavioural dimensions on the conceptualisation and classification of robbery offences are discussed within the existing literature on ‘street’ robbery. Copyright © 2012 John Wiley & Sons, Ltd.