Offender Characteristics: the Constructs of Motives, Personality, and Behavior

As articulated in chapter 7, crime scene evidence is likely to be the only data that a profiling investigator will have to work with when attempting to solve a crime. From these data, the investigator will have to make predictions about the characteristics of an unidentified perpetrator. In considering how to relate pieces of crime scene evidence to offender characteristics within a scientific model of profiling, the direction of causality is likely to be the reverse of the profiling process as conducted in the field. That is, rather than positing that offender characteristics are caused by the pieces of evidence that are left at a crime scene, a scientific profiling model posits that it is an offender's characteristics that lead him to leave particular pieces and patterns of evidence during the commission of his crimes. Therefore, the goal of profiling research on offender characteristics is to empirically examine on a large scale the kinds of offender characteristics that are likely to result in particular pieces or patterns of evidence. Taken together, these offender characteristics constitute three main categories: motive, personality, and behavior. To date, no such large-scale study on offender characteristics has been undertaken. What would be required for this endeavor would be a systematic assessment of a national sample of solved cases, examining the crime scene