Despite the increased use of criminal profiling by law enforcement agencies, few studies examine factors impacting profile accuracy, and only one has evaluated profiler training. The present study examined the efficacy of profiler training on profile accuracy for sexual homicide offenders. Participants (N = 198) were randomly assigned to the training or control condition. Participants in the training condition learned inductive and deductive profiling techniques for sexual homicide offenders, whereas control participants learned about sexual violence prevention. Results indicated that participants’ self-reported use of combined profiling methods produced more accurate profiles. Differences between gender and training groups were also present. These findings suggest brief psychology-based training can be used to teach police officers and detectives to more accurately identify and apprehend criminals.

Swedish national statistics suggest that the number of reported stranger rapes is steadily increasing. Stranger rape is one of the most difficult types of crime for the police to investigate because there is no natural tie between the victim and offender. As a result, there is a need for more knowledge about how crime scene features could be used to make inferences of likely offender characteristics that could help investigators narrow down the pool of suspects. The aim in Study I was to examine how offender behaviors interact with contextual features, victim behaviors, and the assault outcome. Results suggest that the stranger rapes could be distinguished by five different dynamic rape pattern themes, which mainly differed on two dimensions: level of violence to control the victim, and level of impulsivity/premeditation characterizing the rapes. The results also highlight the importance of including contextual features when studying offender behaviors. The aim in Study II was to examine how single-victim rapists and serial rapists can be differentiated by the actions at their first stranger rape. Results suggest that three behaviors in conjunction: kissed victim, controlled victim, and offender drank alcohol before the offense, could be used to predict whether the offender was a single-victim rapist or serial rapist with a classification accuracy of 80.4 %. The aim in Study III was to examine how stranger rapists could be differentiated from a normative sample on background characteristics, and if stranger rapists’ pre-assault and initial-attack behaviors could be used to predict likely offender characteristics. Results showed that the strongest predictions could be made for previous criminal convictions, offender age, and the distance traveled by the offender to offend. Overall, the present thesis has found some scientific support for the use of crime scene behaviors to make inferences of likely offender characteristics that could be useful for profiling purposes. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Submitted. Paper 3: Submitted.</p>

A partir de la fin du XIXe siècle, et notamment à travers les travaux de Richard Von Krafft-Ebing, de nouvelles représentations des perversions sexuelles humaines se mettent en place. La prise en compte de ces dynamiques dans l’homicide modifie les modes de classification des scènes de crime. Au XXe siècle, ces changements historiques conduisent à l’étude d’un phénomène rare et singulier : le meurtre sexuel sériel. Durant les années 1980, le F.B.I acquiert le monopole des savoirs et pratiques concernant la problématique des « serial killers ». De nos jours, ce monopole est remis en cause. Les profileurs du Bureau d’Investigation seraient les représentants d’une pratique pseudo-scientifique. Le serial killer serait avant tout une construction sociale initiée par la politique conservatrice des années Reagan. Selon certains psychiatres-psychanalystes, le F.B.I, en affirmant la place centrale des fantasmes sexuels dans la dynamique des crimes, aurait donné une image trompeuse du meurtre en série. A l’opposé, la présente étude entend démontrer que le principal enjeu n’est peut-être pas de déconstruire les discours du F.B.I, mais plutôt de confronter ces derniers à l’actualité des recherches scientifiques. Le profilage désignerait plutôt une méthode d’enquête dont les éléments de base sont susceptibles d’être corrigés et complétés. Sous cet angle, les modèles théoriques concurrents, notamment ceux défendus par la psychanalyse française, semblent également souffrir d’un certain nombre de difficultés. Certes, l’intensité des fantasmes sadiques ne peut pas être la seule dimension des actes criminels. Mais les fantasmes interagissent probablement avec les désirs et croyances des meurtriers. Si l’homicide sexuel sériel s’apparente, comme la plupart des commentateurs s’accordent à le dire, à une succession d’actes ritualisés, une approche anthropologique du phénomène pourrait avoir une certaine légitimité. Sous cet angle, des concepts tels que la psychopathie, la pulsion de mort ou l’omnipotence narcissique dissimulent peut-être l’existence d’un mécanisme victimaire à travers lequel les meurtriers engendrent leur propre religion ou mythologie. / From the late Nineteenth Century, in particular through Richard von Krafft-Ebing’s studies, new concepts have shaped the representations of sexual perversion. The study of the sexual dynamics in homicide cases changes the common methods of crime scene classification. In the Twentieth Century, these historical approaches lead to the study of a rare and particular phenomenon: serial sexual homicide. During the 1980s, the F.B.I dominates the field of practices and knowledge concerning the serial murder issue. Today, that domination is challenged. The F.B.I’s profiling methods are qualified as pseudo-scientific practice. Serial murder is nowadays more perceived as a simple social construction initiated by the Conservative politics of the Reagan years. According to some psychiatrists, the motivational model of the F.B.I has given a misleading picture of serial murder. The aim of the present work is to show that the main issue may not be to deconstruct the F.B.I’s studies, but to compare these first studies with current scientific research. Criminal profiling might be a method whose basic elements are likely to be corrected and completed. In this perspective, competing theoretical models, especially those held by psychoanalysis, also raise a number of difficulties. Of course, the intensity of sadistic fantasies can’t be the only dimension of criminal behavior. But fantasies probably interact with the desires and beliefs of the murderers. If serial sexual homicide appears to be, as most commentators agree, as a series of ritualistic acts, an anthropological approach may be legitimate. From this point of view, concepts such as “psychopathy”, “death drive” or “narcissism” do probably conceal the existence of a scapegoat mechanism by which killers are creating their own religion or mythology.