Adam J. Carter

Characteristics of non-serial sexual homicide offenders: a review

Abstract A number of issues have complicated the study of sexual killers. Empirical research has not always differentiated non-serial from serial killers or those killers who perpetrate crimes against adults from children or male from female victims. This paper sets out to review studies that have predominantly considered non-serial (where the perpetrator has been convicted for killing one victim) sexual killings of adult females (14 years or older) in terms of childhood, adulthood, victim or crime scene information. Possible characteristics of these perpetrators are identified from relevant literature and these are discussed in terms of assessment and future research.

Toward Identification of the Sexual Killer: A Comparison of Sexual Killers Engaging in Post-Mortem Sexual Interference and Non-Homicide Sexual Aggressors

Establishing a model of sexual assault reflecting psychosocial and behavioral characteristics of perpetrators of sexual killing and rape is necessary for development in risk assessment and intervention. Methodological variations in defining sexual killing have amalgamated serial and non-serial offenders and perpetrators with direct and indirect associations between killing and sexual arousal. This study defined sexual killing specifying that killing should be directly linked to sexual arousal, and sampled 48 sexual killers, operationalized to include only those engaging in post-mortem sexual interference, with one or two known female victims (non-serial), from prison service national (England and Wales) databases. These sexual killers were compared with 48 non-homicide, life or indeterminately sentenced sexual aggressors on psychological and crime scene characteristics. Contrary to previous research, fatal outcomes were associated with neither stranger victims nor weapon presence; sexual killing was characterized by severity of violence less so than non-fatal assault. Sexual killers more often reported problems with emotional loneliness, empathic concern, and sexual entitlement than the sexual aggressors. Theoretical and applied implications are discussed.

A systematic review of the literature comparing male non-serial sexual killers and sexual aggressors: examining homogeneous and heterogeneous characteristics of these groups

ABSTRACT This systematic review considers what is known about the characteristics of sexual killers and sexual aggressors. The aim was to identify which characteristics have consistently been shown to be similar (homogeneous) and which are different (heterogeneous) across these two groups. Ten studies, including approximately 300 sexual killers, were analysed. Only studies where the samples were directly compared and where sexual killers were male, predominantly non-serial and perpetrated against adult female victims were included. Results indicate that levels of loneliness and anger appear to be more prevalent in the sexual killer sample while mental health disorders, criminal history, family structure and history of sexual abuse as well as some crime scene behaviours seem to be similar across the two groups. The results of this review have also highlighted some methodological problems inherent to these types of studies and these issues are discussed from the perspective of improving research on these crimes.

The Use of Crime Scene and Demographic Information in the Identification of Non-Serial Sexual Homicide

As with other sexual offenders, sexual homicide perpetrators can be reluctant to talk about their criminal behavior. Therefore, in homicide cases, forensic practitioners frequently rely on crime scene information to identify any sexual behavior associated with the offense. This study aims to identify objective and readily available crime scene information, alongside information about victims and perpetrators, based on 65 cases from England and Wales in the United Kingdom of men convicted of homicide who had committed a non-serial sexual homicide and 64 cases of men convicted of homicide where the available evidence indicated that it was a non-serial non-sexual homicide. Chi-square tests and logistic regression were used to analyze the data. There were few differences in terms of demographic information and criminal histories between the two perpetrator groups. There were crime scene indicators supporting the use of Ressler et al.’s definition of sexual homicide. The victims of sexual homicide were generally found in their home with the lower half of the body exposed and with evidence of vaginal sex. Furthermore, extreme injuries and strangulation were more frequent in sexual homicides. Use of weapon was associated with a non-sexual homicide. Victims of sexual homicide were as likely to know the perpetrator as not. Potential benefits of the characteristics reported to investigators and forensic practitioners tasked with identifying sexual homicides are discussed and areas for further research suggested.

The Strengths of Treatment for Sexual Offending

It is not disputed that sex offender treatment could be more effective in terms of reducing reoffending. However, enhancing effectiveness does not necessarily mean we need to start again entirely in designing programmes. This chapter will discuss in what ways we have got sex offender treatment “right”. Applying the principles of evidence-based practice, which elements of sex offender treatment programmes, as typically described, “pass the test”? Which treatment targets, and which treatment methodologies, have been empirically tested and found to be appropriate and effective? Drawing on meta-analyses, individual outcome studies, participant feedback studies and evaluations using intermediate outcomes such as attitudinal change, the chapter considers what we know about what works with sex offenders, in terms of who benefits from programmes, what programmes should target and how programmes should be delivered. We conclude that few components of typical sex offender programmes can be described as evidence based, some are evidence informed in that they are theoretically sensible but under-researched, and some are unlikely to be effective. One problem might be the expectation that treatment programmes can stand alone as the method by which reoffending is reduced. Instead, it is likely that programmes need to be delivered in a wider context that supports personal change and provides social and emotional support beyond the confines of the therapy room.

In defence of NOMS' view about sex offending treatment effectiveness: A reply to Ho and Ross

We would like to thank the editor for inviting us to respond to this editorial. It seems a rather surprising attack on what we had thought to be a benign and accessible summary of the sex offending treatment effectiveness literature. The ‘fact sheet’ to which Ho and Ross refer is a document produced by National Offender Management Service (NOMS) staff firstly for staff working in prisons and probation and secondly for the many external/public enquiries about what prison and probation services are doing to reduce sexual offending. In producing this document, our main aim was to help readers become familiar with the broad findings in this area and to provide references to the main studies for further reading. The NOMS document summarises the conclusions of studies. Meta-analyses combining two or more evaluations studies with strong designs were considered the highest form of evidence, and these were the only types of studies summarised in the ‘International Evidence’ section. Where no meta-analyses were available, as is the case in relation to prison and probation programmes specifically in England and Wales, we described the individual studies, ensuring that in each case the design was made clear. When researchers are embedded with policy makers, there is always the danger of unintended partiality, and we are very conscious of this. Hence, as is our usual practice with evidence summaries as well as with formal research reports, we obtained a peer review of the document before issuing it. The peer reviewer in this case was an independent academic expert on the effectiveness of correctional programmes, who had no allegiance to or involvement with the delivery of treatment to sexual offenders. We will now comment on the eight statements which, according to Ho and Ross, are controversial:

Einige Vorschläge zu Ordnungsprinzipien für die Behandlung von Sexualdelinquenz

Viele Behandlungsprogramme fur Sexualstraftater konzentrieren sich anscheinend auf Ziele, die vielleicht gar keine Verbindung zu den Risiken haben, und dies manchmal auf Kosten empirisch untermauerter Risikofaktoren. Dieses Kapitel betrachtet mogliche Grunde fur solche Lucken zwischen wissenschaftlichen Nachweisen und der Behandlungspraxis. Anschliesend werden ein Veranderungsmodell und einige Ordnungsprinzipien fur Behandlungsprogramme dargelegt, um diese an die Risiko-, Bedurfnis- und Ansprechbarkeits-Prinzipien der Straftater-Resozialisierung anzukoppeln und auch die biologischen, psychologischen und sozialen Faktoren zu berucksichtigen, die sexuelle Straffalligkeit unterstutzen.

Sadism among sexual homicide offenders: Validation of the Sexual Sadism Scale.

Sexual sadism is assumed to be a crucial factor in sexual homicide. Prevalence estimates vary greatly due to differences in the definition of sexual sadism. A nationwide sample of 350 male perpetrators who had committed a sexual homicide offense against a female 14 years of age or above in England or Wales was assessed based on archival records. Sexual sadism was assessed using the Sexual Sadism Scale (SeSaS). Item response theory (IRT) analyses were conducted focusing on the 2-parameter logistic model. The single-factor structure of the SeSaS Part 1 was tested using confirmatory factor analysis. Estimates of both internal consistency and interrater agreement were satisfactory to substantial. IRT analysis showed that the Part 1 items captured moderate to severe levels of the latent construct (i.e., theta levels >0). Based on the Posterior Probability of Diagnosis index, the prevalence of the disorder was estimated at 37% in the sample. The substantial correlation between the SeSaS Part 1 total score and original clinical diagnoses of sadism confirms the criterion validity of the scale. Exertion of control and infliction of torture were among the more informative items. In sum, the results support the usefulness of the SeSaS instrument for assessing forensically relevant forms of sadism.

“We Boil at Different Degrees”: Factors Associated With Severity of Attack in Sexual Killing:

Degree of injury, as measured by the Homicide Injury Scale (HIS), was examined to advance understanding of the dynamics of sexual killing. A total of 350 nonserial, male sexual killers were included, and the different ways that the sexual element of their offenses and the act of killing were connected was accounted for by determining that cases were either directly sexual (the sexual element and killing were closely bound), or indirectly sexual (killing was not a source of sexual stimulation). The two groups, direct and indirect sexual killers, were each subjected to multiple linear regression analyses to examine the group-specific relationship between level of injury and predictor variables previously found to be associated with increased severity of attack. No differences in the mean total HIS scores between the indirect and the direct cases were found, suggesting a comparable emotional intensity between the groups. However, given that the groups differed in terms of the functional role of fatal violence, severity of attack could not be sufficiently explained as driven by anger. In line with this hypothesis, different predictors appeared to be associated with increased degree of injury sustained by victims of indirect compared with direct sexual killers. As such, situational components appear to play a role in the behavior of indirect sexual killers, whereas the behavior of direct perpetrators tends to be linked with the enactment of existing deviant fantasies. The role of anger in sexual homicide is discussed further, and overall, it is argued that irrespective of whether violence was initially driven by anger, evidence of sexual arousal to severe violence must be scrutinized within sexual homicide research as well as in psycholegal contexts.