Untangling sexual homicide: A proposal for a new classification of sexually motivated killings

Purpose: The study aimed to develop an empirically driven checklist guiding clinicians in the decision-making process that would enable them to determine the functional role of the killing in a newly proposed classification of sexual homicides.

Methods: Classical Test Theory, Exploratory Factor Analyses and Two-parameter item response theory were conducted on a sample of 361 male sexual killers assigned as either belonging to the direct or indirect group.

Results: The results revealed that an eight-item checklist was the best empirical solution. The items included: sexual sadism; followed by the use of sexually related disinhibitors; stalking behaviours; the use of restraints; the presence post-mortem sexual activity; the presence of other sexual activities; an unusual interest following the murder; and the presence of biting were indicative of a direct sexual homicide.

Conclusions: Using the direct/indirect typology automatically directs clinicians to consider how, and at what point in the timeline, the sexual element and the act of killing were related. This, allows to address any arising inconsistencies as well as minimise the risk of either assuming sexual motives in the killing in the indirect cases or not addressing management of sexual urges in the context of extreme violence for the direct cases.