Comparing Crime Scene Trajectories: Sexual Versus Nonsexual Serial Homicides

When faced with a possible serial offender, crime linkage analysis is crucial in identifying which crime scenes belong to the same offender. Thus, when analyzing behavioral consistency to link crimes, it is essential to use a classification model that is empirically tested and is based on the type of crime being investigated. Several classification models examine patterns of consistency and change using a combination of thematic and behavioral subgroups; however, they are tested using sexual and nonsexual crime scenes, which some recent literature argues are two distinct types of homicide and should be examined separately. The present study tests the theoretical assumption that sexual and nonsexual homicides are different enough to warrant a separate examination by (1) comparing the occurrence of salient behaviors between sexual (n = 47 crime scenes, 11 unique offenders) and nonsexual (n = 31 crime scenes, 7 unique offenders) crime scenes; (2) comparing their themes of behavior; and (3) using the Model for the Analysis of Trajectories and Consistency in Homicide (MATCH) (Salfati & Sorochinski, 2019) to compare the patterns of thematic change and behavioral consistency. The results show that sexual and nonsexual serial homicide offenders differ in their crime scene actions and behavioral themes. The psychological implications and future directions are discussed