Offender profiling

• What is offender profiling?

  Gathering info from crime scenes in order to predict who committed the crime and help to catch the perpetrators
• Which country uses the top down approach?

  USA
• How was the top down approach established?

  Interviewing 36 serial killers in the 1970s
• How is the top down approach done?

  Assess the crime scene, theorise about the perpetrator and categorise them as 'organised' or 'disorganised'
• What are characteristics of organised perpetrators?

  Higher education, calculated crime, high control over emotions (psychopaths/sociopaths)
• What are characteristics of disorganised perpetrators?

  Careless, lower education, crimes of passion
• Data assimilation

  Evidence gathered: interview witnesses, CCTV, photos, forensic evidence, police reports
• Crime scene classification

  Decide whether it's an organised or disorganised crime
• Crime reconstruction

  Hypotheses are made about what happened during the crime, victim behaviour and the sequence of events
• Profile generation

  Profile is made based on social groups and treats
• The Top down approach

  1. Data assimilation
  2. Crime scene classification
  3. Crime reconstruction
  4. Profile generation
• What is the bottom up approach?

  Generating a picture of the offender through crime analysis. Investigative psychology and geographical profiling
• Who developed investigative psychology?

  David Canter
• What is investigative psychology?

  Statistical analysis of behaviour and geography
• Interpersonal coherence

  Due to consistency in human behaviour, there are correlations between crime elements and everyday behaviour
• Forensic awareness

  Link between behaviour and past experience
• Space analysis

  Crime scene location and offender characteristics are correlated
• Geographical profiling

  Plots crimes on a map to detect patterns or areas of similar crimes
• What are the weaknesses of the top down approach?

  • Best suited to crimes that reveal something about the perpetrator (rape, burglary), less generalisable to less personal crimes (fraud, tax evasion)
  • Small sample- only 36 serial killers, self report is unreliable
• What are the strengths of the top down approach?

  • Copson (1985) found 82% of US officers found it useful
  • Can help public manhunts
• What are the strengths of the bottom up approach?

  • Godwin and Carter found 85% of offenders lived in the circle
  • Scientific- based on psychological theories and research
• What are the weaknesses of the bottom up approach?

  • Koscis and Irwin only 50% of burglars lived in the circle
  • Western research- may not be generalised
  • Under reporting and police records limit effectiveness