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In serial homicide in order to link crimes to a common offender it is essential to classify the offender based on classes of action at the crime scene which relate to a particular sub-group of offenders (Canter, 2004). This classification should be reliable and empirically tested to support the assignment of cases to one group or another. The classification system should also meet the assumptions of a typology which specify that the characteristics that define a type within a typology must co-occur together frequently, and the characteristics specific to one type must not occur frequently with the characteristics specific to another type (Canter, 2004).
Much of the focus of criticism surrounding the FBI process of profiling focuses on the validity of the classification stage, and in particular the organised/ disorganised dichotomy and its theoretical and empirical foundations and assumptions (Alison, Bennell, Mokros & Omerod, 2002). This dichotomy has become one of the most commonly cited and used classifications of violent, serial offenders (Woodworth & Porter, 2002). The only available study which examines the interrater reliability of the classification system used by the FBI involved the reading of a case summary of sexual homicide by a profiler and the classification of the offender by profiling trainees (FBI, 1985). In this study interrater reliability was found to be between 51.7% and 92.6%. This study, although dated, does provide limited support for the reliability of the FBI sexual homicide classification system. However, this form of reliability contributes little to the usefulness of the offender profiling system if the classification used lacks validity or predictive utility.
In regard to the validity, the FBI classification system is derived from a single interview-based research study with a small sample of apprehended serial killers who operated in North America (25 selected from an original sample of 36) (FBI, 1985; Turvey, 1999). The generalisability or ecological validity of the FBI's classification system considering the limitations of such a sample (e.g. small, culture specific) is questionable. Further limitations of the original study include; the subject selection process which relied on non-random self-selection, and the extensive use of potentially fallible self-report data (Beasley, 2004). The interviews were also unstructured and developed in an ad hoc fashion which was dependent on the interviewees (Canter, Alison, Alison & Wentink, 2004). The process whereby participants were divided into groups based on organised or disorganised characteristics and behaviours has been described as the product of circular reasoning, involving the “reification of a concept” in contrast to an empirical validation of this concept.
The organised/ disorganised dichotomy, is further flawed in that it fails to meet the criteria of a typology (Canter, 2004). Canter examined the relationship between the behavioural styles and background characteristics of 100 serial homicides/offenders using a multi-dimensional scaling (MDS) procedure called Smallest Space Analysis (SSA) which statistically represents the co-occurrence of variables. No evidence was found to support the co-occurrence of behavioural styles or background characteristics related to the organised/disorganised taxonomy as proposed in the Crime Classification Manual (CCM).
See also Edit
Source Articles Edit
Alison, L., Bennell, C., Mokros, A., & Ormerod, D. (2002). The Personality Paradox in Offender Profiling: A Theoretical Review of the Processes Involved in Deriving Background Characteristics From Crime Scene Actions. Psychology, Public Policy, and the Law, 8(1): 115-135.
Beasley, J.O. (2004). Serial Murder in America: Case Studies of Seven Offenders. Behavioral Sciences and the Law, 22: 395-414.
Canter, D. (2004). Offender Profiling and Investigative Psychology. Journal of Investigative Psychology and Offender Profiling, 1: 1-15.
Canter, D., Alison, L.J., Alison, E., & Wentink, N. (2004). The Organized/ Disorganized Typology of Serial Murder: Myth or Model? Psychology, Public Policy, and Law, 10(3): 293-320.
Federal Bureau of Investigation. (1985, August). The Men Who Murdered. FBI Law Enforcement Bulletin, 2-31. As cited in Beasley, J.O. (2004). Serial Murder in America: Case Studies of Seven Offenders. Behavioral Sciences and the Law, 22: 395-414.
Turvey, B.E. (1999). Criminal Profiling: An Introduction to Behavioural Evidence Analysis. San Diego: Academic.
Woodworth, M., & Porter, S. (2001). Historical Foundations and Current Applications of Criminal Profiling in Violent Crime Investigations. Expert Evidence, 7: 241-261.
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