Offender Profiling Hypothesis

Traditionally, offender profiling has been defined as ‘the process of using all the available information about a crime, a crime scene, and a victim, in order to compose a profile of the (as yet) unknown perpetrator’ (Ainsworth, 2001, p. 7). Offender profiling is an investigative tool which determines offender characteristics from the scene of crime. It is an inferential process involving the analysis of offender behaviour, their interactions with the crime scene, the offender and their choice of weapon among other things (Petherick, 2003). Such inferences are made with the intention of assisting law enforcement personnel throughout their investigations. An underlying rationale concerning offender profiling is that behaviour will reflect personality,

Although there is limited evidence and published studies to support this hypothesis, the marjority of supporting research originates from the field of case linkage. One such study, conducted by Salfati & Bateman (2005) aims to determine if serial homicide offenders are consistent across their series of homicides in their crime scene behaviours. Within the study, 35 serial homicide behaviours utilized by 90 offenders in 450 serial homicide cases were carried out to identify whether offenders performed the same behaviours consistently throughout their series of homicides. They evaluated six conditions of frequency and consistency; weapon behaviours, stealing property behaviours, sexual behaviours, mutilation behaviours, planning and control behaviours and body disposal behaviours, and found that behaviours were consistent in all conditions. In another study, Grubin, Kelly, and Brunsdon (2001) assessed the importance of behavioural consistency in serial sexual offenses. They statistically developed four offense domains of behaviours relating to the control methods, the sexual aspects of the offenses, escape mechanisms and the offense style used by the offender. Researchers evaluated the series of crimes each offender committed to determine whether (s)he was likely to consistently perform the same type of behaviour under the domain in question. The results from this study indicated that serial sexual assault offenders consistently employed some of their behaviours across their series of assaults. The possibility of linking a series of crimes is perceived to be beneficial to law enforcement bodies such as the police as it enables information to be collated across multiple crimes therefore increasing evidence against an offender, strengthening a case (Labuschagne,