Profilers - Definitions

Definitions

Offender profiling is a method of identifying the perpetrator of a crime based on an analysis of the nature of the offense and the manner in which it was committed. Various aspects of the criminal's personality makeup are determined from his or her choices before, during, and after the crime. This information is combined with other relevant details and physical evidence, and then compared with the characteristics of known personality types and mental abnormalities to develop a practical working description of the offender.

Psychological profiling may be described as a method of suspect identification which seeks to identify a person's mental, emotional, and personality characteristics (as manifested in things done or left at the crime scene). This was used in the investigation of the serial murders committed by Ted Bundy. Dr. Richard B. Jarvis, a psychiatrist with expertise on the criminal mind, predicted the age range of Bundy, his sexual psychopathy, and his above average intellect.

A further, more detailed example of how psychological profiling may be performed is the investigation of Gary Leon Ridgway, also known as the Green River Killer. This case also demonstrates the potential for incorrect predictions. John E. Douglas, an investigator who worked for the FBI, provided a twelve-page profile, which stated the suspect was:

• Probably a white male who had a dysfunctional relationship with women.
• Organized since he tried to hide the bodies and appeared to spend some time at the river
• Cunning in using rocks to weigh the victims down in the water to conceal them.
• Very mobile with a vehicle.
• Going to kill again.
• Like other serial killers, he would be prone to contacting police wanting to help in the investigations.

However, the profile created for Ridgway also revealed characteristics that did not apply to him, such as being an outdoorsman and being incapable of closeness to other people. Ridgway was not an outdoorsman, but frequented the Green River with one of his wives, and also had a very close relationship with his last wife, which contradicted the point in the profile of being incapable of closeness.

One type of criminal profiling is referred to as linkage analysis. Gerard N. Labuschagne (2006) defines linkage analysis as "a form of behavioral analysis that is used to determine the possibility of a series of crimes as having been committed by one offender." Gathering many aspects of the offender’s crime pattern such as modus operandi, ritual or fantasy-based behaviors exhibited, and the signature of the offender help to establish a basis for a linkage analysis. An offender’s modus operandi is his or her habits or tendencies during the killing of the victim. An offender’s signature is the unique similarities in each of his or her kills. Mainly, linkage analysis is used when physical evidence, such as DNA, cannot be collected.

Labuschagne states that in gathering and incorporating these aspects of the offender’s crime pattern, investigators must engage in five assessment procedures: (1) obtaining data from multiple sources; (2) reviewing the data and identifying significant features of each crime across the series; (3) classifying the significant features as either MO and/or ritualistic; (4) comparing the combination of MO and ritual/fantasy-based features across the series to determine if a signature exists; and (5) compiling a written report highlighting the findings.