Psychological profiler

Offender profiling, also known as criminal profiling, is an investigative tool used by law enforcement agencies to identify likely suspects (descriptive offender profiling) and analyze patterns that may predict future offenses and/or victims (predictive offender profiling). Offender profiling dates back to 1888 and the spree of Jack the Ripper, and the profiling theory describes how profiling will ideally work. Current applications include predictive profiling, sexual assault offender profiling, and case linkage (using profiling to identify common factors in offenses and to help with suspect identification).

Goals of criminal profiling include providing law enforcement with a social and psychological assessment of the offender; providing a "psychological evaluation of belongings found in the possession of the offender" (p. 10); and offering suggestions and strategies for the interviewing process. Ainsworth (2001) identified four main approaches to offender profiling: geographical, investigative psychology, typological, and clinical profiling.

Five steps in profiling include analyzing the criminal act and comparing it to similar crimes in the past, an in-depth analysis of the actual crime scene, considering the victim’s background and activities for possible motives and connections, considering other possible motives, and developing a description of the possible offender that can be compared with previous cases. Notable profilers in history include Ernst Gennat, Walter C. Langer, James Brussel, Howard Teten, Robert Keppel, Richard Walter, John Douglas, Robert Ressler, and David Canter.

Entertainment media has depicted the practical use of offender profiling through television shows such as Law & Order: Criminal Intent, Law & Order: Special Victims Unit, Profiler, Criminal Minds, Criminal Minds: Suspect Behavior, Criminal Minds: Beyond Borders, and the 1991 film The Silence of the Lambs. Unlike these and other popular media portrayals, offender profiling is just one of the tools, investigative methods, and techniques available to law enforcement personnel. Offender profiling is still controversial and subject to debate and varied opinions about the accuracy of, effectiveness of, evidentiary support for, and scientific validity and reliability of this investigative tool.

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