Linking behaviour to characteristics: Evidencebased practice and offender profiling - PowerPoint PPT Presentation

1 / 25
About This Presentation
Title:

Linking behaviour to characteristics: Evidencebased practice and offender profiling

Description:

Linking behaviour to characteristics: Evidence-based practice and offender profiling ... Victorian Institute of Forensic Mental Health (Forensicare) ... – PowerPoint PPT presentation

Number of Views:109
Avg rating:3.0/5.0
Slides: 26
Provided by: michae762
Category:

less

Transcript and Presenter's Notes

Title: Linking behaviour to characteristics: Evidencebased practice and offender profiling


1
Linking behaviour to characteristics
Evidence-based practice and offender profiling
  • Michael R. Davis
  • School of Psychology, Psychiatry, and
    Psychological Medicine, Monash University,
    Australia
  • and
  • Victorian Institute of Forensic Mental Health
    (Forensicare)

2
  • Let me make it very clear, poor people arent
    necessarily killers.
  • Just because you happen to be not rich doesnt
    mean youre willing to kill
  • - George W. Bush (May 19, 2003)

3
Crime Classification Manual(Douglas, Burgess,
Burgess, Ressler, 1992)
  • Homicide, Arson, Sexual Assault
  • Detailed DSM-type classification
  • Potential profile information
  • At present there have been no systematic efforts
    to validate these profile-derived
    classifications (p. 22)
  • We want to emphasizethat this rationally
    derived system has not yet beentested (p. 22)

4
Sexual Homicide(Ressler et al., 1986, 1988)
  • Organised/Disorganised - 36 murderers interviewed
  • Organised
  • Scene planning, controlling, sexual acts with
    live victim
  • Offenders intelligent, skilled job, angry
    depressed
  • Disorganised
  • Scene position dead body, necrophilia,
    depersonalisation
  • Offenders low birth-order, know victim,
    confused, live alone
  • Problems with statistical analyses

5
Profiling expressed as a Canonical Equation(See
Canter, 1995 Youngs, 2004)
  • B1A1 B2A2 BnAn D1C1 D2C2
    DnCn
  • Where
  • A Actions during offences
  • C Characteristics of offender
  • B and D weightings

6
Organized
Disorganized
7
Homicide
  • Sexual homicide of elderly (Safarik et al., 2000,
    2002)
  • White victims more likely to be attacked by black
    offenders
  • Race, age, distance from house predictable
    (approx 70 accuracy)
  • Sexually-oriented child homicide (Aitken et al.,
    1995)
  • Age, previous convictions, victim-offender
    relationship predictable
  • Classification rate gt 70
  • U.S. Serial killings (Hodge, in press)
  • SSA (thematic structure of crime scene actions)
  • Themes of offender-victim interaction
  • Victim viewed as an object, vehicle, or person

8
Stranger Homicide (Salfati, 2000a, 2000b
Salfati Canter, 1999)
  • Instrumental and expressive offence actions
  • Three themes (65 classified)
  • Expressive (impulsive)
  • Married, previous violent, property, sexual,
    drug offences
  • Instrumental (Opportunistic)
  • Previous offences for burglary, unemployed,
    familiar with area
  • Finnish Stranger Homicides (Santtila et al.,
    2003)
  • Instrumental offenders unlikely to confess

9
Sexual Assault
  • FBI rape typology (Warren et al., 1991)
  • Power and anger motivations
  • Behaviour classified as proposed by typology
    (71-91 of cases)
  • Increased violence in subsequent rapes
    predictable
  • Excessive binding, Prolonged Transport, No
    negotiation, Macho

10
Evaluation of FBI Rape Typology(Bennett, Ogloff,
Davis, in prep)
ANGER
POWER
11
Evaluation of FBI Rape Typology(Bennett, Ogloff,
Davis, in prep)
ANGER
POWER
12
Evaluation of FBI Rape Typology(Bennett, Ogloff,
Davis, in prep)
ANGER
POWER
11-39
13
Evaluation of FBI Rape Typology(Bennett, Ogloff,
Davis, in prep)
ANGER
POWER
5-10
11-39
14
Thematic classification of rape(Canter, Bennell,
Alison, Reddy, 2003)
15
Sexual Assault
  • Links with characteristics
  • History of burglary (Canter et al., 1991 Davies
    et al., 1998)
  • Higher levels of violence in rape linked to
    personality disorder
  • Sadistic schizoid, avoidant, dependent
  • Opportunistic antisocial, narcissistic, paranoid
  • (Proulx et al., 1994, 1999)

16
Arson
  • FBI-motivational typology (Icove Estepp, 1987)
  • Classification supported by 1016 interviews
  • Empirical classification four themes
    (Canter Fritzon, 1998
    Fritzon, 1998 Fritzon et al., 2001)
  • Instrumental and expressive arson
  • Person or object focussed
  • Four corresponding themes of background
    characteristics
  • Supported in active case (Santtila et al., 2003)

17
Conceptual model of offender profiling
information
  • Demographic
    Offending
  • Characteristics Behaviour

18
Conceptual model of offender profiling
information
  • Personality
    Offending
  • Behaviour
  • Demographics

19
Conceptual model of offender profiling
information
  • Situational
  • Influences
  • Personality
    Offending
  • Behaviour
  • Demographics

20
Conceptual model of offender profiling
information
  • Situational
  • Influences
  • Personality
    Offending
  • Behaviour
  • Demographics

21
Progress in geographical profiling is more rapid
  • Data is more precise
  • Attack or disposal sites are obviously influenced
    by the situation, but less so than interpersonal
    behaviour
  • Theoretically barren use of demographics is not a
    component of the calculations

22
Future research directions
  • Determine offence behaviours least influenced by
    situational factors
  • Respondent vs operant behaviour
    (Funder Colvin, 1991
    McClelland, 1984)
  • Focus on personality traits
  • Hypotheses from existing SSA plots
  • Causal-theoretical statistics
  • Interviews with offenders
  • Well-validated personality inventories
  • Determine conditional traits (Alison et al.,
    2002 Wright Mischel, 1987)

23
Future research directions
  • Personality (Youngs, 2004)
  • 207 young offenders
  • Delinquency and personality questionnaires
  • Expressive/instrumental and person/property
    distinction
  • Expressive-person related to power and control
  • Property offenders perceived more controls from
    others
  • Offenders targetting people perceived more
    emotional closeness
  • Decision-making in individual profiles
  • Determine situations where research is inaccurate
  • Beneficial for theory development

24
Conclusion
  • Current empirical literature
  • Broad demographic features themes of
    interaction
  • Purely actuarial approach not feasible
  • Structured Professional Judgment (Davis, 2003)
  • Use empirical evidence to anchor inform
    judgment
  • Add to vary opinion based on case-specific
    features
  • Base variations on theory or clearly explained
    deduction (rather than intuition)
  • Clear parallels with pragmatism (Alison, 2005)

25
(No Transcript)
Write a Comment
User Comments (0)
About PowerShow.com