Goals of the Workshop. Criminal personality profiling: State of the science. Conflict of Interest. September 30, 2012

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1 Criminal personality profiling: State of the science 6925 Union Park Center, Suite 550 Cottonwood Heights, Utah Mark Zelig, Ph.D., ABPP Independent Practice 4325 Laurel St., Suite 297 Anchorage, Alaska Conflict of Interest I have not received support or incentives from any drug, equipment, psychological testing entity, or other company. The limitations of research will be offered throughout the workshop I provide CE workshops for: Alta Psychological Services United States Government APA Other organizations from time to time 3 Goals of the Workshop Discuss the newest developments in crime scene consultation that is supported by scientific data. Provide a brief overview of the statistical methodologies that t have fueled the progression of the science. Offer practical recommendations for engaging in this type of forensic psychology consultation. 4 1

2 Crime scene consultation occurs at the investigative and trial levels Investigative level: Questions: What investigative approaches are likely to yield evidence and case resolution? What identifiable characteristics is the offender likely to possess? What is the likelihood that the offender of Crime A, did Crimes B and C? 5 Crime scene consultation occurs at the investigative and trial levels Investigative level: Goal: Avoid false negative errors. Potential harm: Leading investigation astray, stigmatizing innocent subjects; facilitating false confessions. 6 Crime scene consultation occurs at the investigative and trial levels Trial and sentencing level: Questions: What was the intent or state-of-mind of the defendant? (e.g., mens rea, mitigation, etc)? Can you rebut the testimony of another expert who stated that the offender s behavior is (in)consistent with the alleged offense? Goal Avoid false positive errors. Potential errors False conviction of defendant which may also allow actual offender to elude apprehension. International Association of Chiefs of 7 2

3 How accurate is crime scene profiling? Illustrative findings Ressler et al. (1988): At present there have been no systematic efforts to validate these profile derived classifications (p. 22). Alison et al (2003) looked at 21 actual profiles of solved cases hypotheses generated 20% of the hypotheses were subsequently supported by the evidence. 8 Why this outcome? Sampling: Real world cases do not emerge from a random sample. Bias: Collected information is biased per the needs of the observer. Lack of definition of observable variables thwarts the development of research. Discriminating salience: Investigators and consulting psychologists may have difficulty discriminating unique from common criminal behaviors. 9 Which three of the following events occurred at least 50% of the time in single-victim homicides in the UK? Face visible Victim found in water Victim found at the same scene where he or she was killed Multiple wounds to one body area Victim drugged and/or poisoned Blindfolded (Salfati, 2003, pp ) 10 3

4 Actual Smallest Space Analysis International Association of Chiefs of 11 Smallest space analysis (adapted from Salfati, 2003) Face Scene Multiple Water Blind Drugged International Association of Chiefs of 12 Linkage analysis: Assumptions and obstacles What is the likelihood that the offender of Crime A was involved in Crime B? Two-part assumption: (1) The offender exhibits behaviors that differentiate them from other offenders, and (2) the idiosyncratic behaviors will be observed in other crimes. 13 4

5 Linkage analysis: Assumptions and obstacles What is the likelihood that the offender of Crime A was involved in Crime B? Obstacles and workarounds: Samples are limited to arrested offenders and to crimes in which there is evidence of their (non) involvement. Lemmers et al. (2012): Compared apprehended offenders to nonapprehended offenders using Dutch DNA data bank. Probability of arrest increases with number of offenses. Probability of arrest decreases with specialization in crime. 14 Linkage analysis: Assumptions and obstacles What is the likelihood that the offender of Crime A was involved in Crime B? Obstacles and workarounds: What aspects of a crime reflect situational characteristics versus the offender s traits? One of the ways that psychologists attempt to make this discrimination is by learning about the victim s characteristics. Is analysis based on behaviors (e.g., binding) vs. themes (e.g., controlling)? (Salfati, 2011, p. 131). International Association of Chiefs of 15 Linkage analysis Illustrative research studies Harbers et al. (in press) analyzed 347 sexual assaults committed by 69 serial rapists Consistency could be measured using Jaccard s (1908) coefficient and became more prominent as the number of sexual assaults increased. This outcome is consistent with Sorochiniski and Salfati s(2010) findings. Deslauries-Varin & Neauregard (2010), N = 72 serial rapists: 50% chose an exclusive type of victim and the others selected a diversity of victims. International Association of Chiefs of 16 5

6 Recommendations Do a walk-through if the crime scene is still available. Apparent inconsistencies can be resolved. Do no harm! Place explicit disclaimers including a statement that it is very unlikely that all hypotheses are accurate. Desperation in investigations fuels decision and judgment errors (Zelig, 2006). Acknowledging cultural differences is more than being politically correct: It can help solve crimes. 17 Recommendations Don t back yourself against a wall: Avoid the word profile the word is inaccurate and may be considered character evidence, which is generally excluded in a trial. If case goes to trial, plan to be called as the opposing side s witness. Place explicit disclaimers including statements that it is very unlikely that all hypotheses will be proved to be accurate. 20 Recommendations In real life, these investigations go on for years: Be mindful that there is no expiration date on your evaluation. State propositions as hypotheses. 21 6

7 References Alison, L., Smith, M. D., Eastman, O., & Rain- Meyer, C. B. (2007) Toulmin's philosophy of argument and its relevance to offender profiling. Psychology, Crime & Law, 9, Deslauriers-Varin, N., & Beauregard, E. (2010). Victims routine activities and sex offenders target selection scripts: A latent class analysis. Sexual Abuse: A Journal of Research and Treatment, 22, Godwin, G. M. (2000). Hunting serial predators: A multivariate classification approach to profiling violent behavior. Boca Raton, FL: CRC Press. Harbers, E., Deslauriers-Varin, N., Beauregard, E., & van der Kemp, J. J. (in press). Testing the behavioural and environmental consistency of serial sex offenders: A signature approach. Journal of Investigative Psychology and Offender Profiling. Jaccard, P. (1908). Nouvelle recherches sur la distribution florale. Bulletin de la Societe Vaudoise des Sciences Naturelles, 44, References Lammers, M. Bernasco, W., & Elffers, H. (2012). How long do offenders escape arrest? Using DNA traces to analyze when serial offenders are caught. Journal of Investigative Psychology and Offender Profiling, 9, Ressler, R. K., Burgess, A. W. & Douglas, J. E. (1988). Sexual homicide: Patterns and motives. Lexington: Lexington Books. Salfati, C. G. (2011). Criminal profiling. In B. Rosenfeld & S. D. Penrod (Eds). Research methods in forensic psychology. (pp ). New York: Wiley. Sorochiniski, M., & Salfati, C. G. (2010). The consistency of inconsistency in serial homicide: Patterns of behavioural change across series. Journal of Investigative Psychology and Offender Profiling, 7(2): Zelig, M. (2006, June 9). Homicide clearance rates: Have we ignored the role of cognitive variables in the investigative process? Presented at the Annual Meeting of the Homicide Research Working Group, Richmond, VA. 23 7