offender profiling

• offender profiling


  a method to understand why a criminal committed the crime and things about the criminal
• two types of offender profiling

  • top down approach
  • bottom up approach
• top down approach

  used by FBI, intuition approach, starts with established typology and assigns individuals to them, based on witness accounts and evidence
• bottom up approach


  british model, statistical approach, develops a likely hypothesis about the offender
• in the top down approach there are two types of offender…

  organised or disorganised
• FBI interviewed…

  36 convicted murderers - 24 organised offenders, 12 disorganised offenders
• organised offenders:

  offence planned, moves body, uses restraints
• disorganised offenders:

  offence is spontaneous, random, messy, leaves the body, minimal restraints
• there are 4 stages in the top down approach

  • data assimilation
  • crime scene classification
  • crime reconstruction
  • profile generation
• data assimilation


  profiling input: data collected about crime and crime scene

  decision process models: organise into patterns - murder type etc
• crime scene classification


  crime assessment: organised or disorganised?
• crime reconstruction


  criminal profile: profile constructed about events, including hypothesis
• profile generation


  crime assessment (2): written report, profile evaluated

  apprehension: profile generating - review to check conclusions
• bottom up approach was developed by

  david canter and uses investigative psychology and geographical profiling
• david canter created a 5 factor model

  • interpersonal coherence
  • time and place significance
  • criminal characteristics
  • criminal career
  • forensic awareness
• interpersonal coherence 


  people are consistent in their behaviour and there will be correlations with aspects of the crime

  for example, life - martial arts specialist, crime - martial arts moves
• time and place significance 


  location has ties to mental schemas, likely to feel comfort and feel in more control here
• forensic awareness


  does the criminal show knowledge of the justice system or previous techniques
• forensic awareness example


  davies et al (1997) - found rapists who conceal fingerprints often had experiences with burglary — burn fingers deliberately
• criminal career

  MO (modus operandi) changes due to having more experience
• modus operandi


  a distinct way a criminal commits a crime
• small space analysis


  data about crime scenes and offender are correlated and analysed to produce underlying theme
• two parts to the bottom up approach

  • investigative psychology
  • geographical profiling
• geographical profiling 


  assumes locations of crime is not random, not focused on physical characteristics, helps to narrow down search areas
• least effort principle


  multiple equal potential locations, but offenders pick one closest to their home base
• distance decay


  number of crimes decrease further away from home base, a buffer zone around home base to decrease chances of being recognised
• circle theory


  offenders have spatial mindset and commit crimes in an imagined circle
• two types of offender (circle theory)

  marauders and commuters
• marauders 


  commit crimes within the circle
• commuters


  travel outside the circle to commit crime
• circle theory is considered to be simplistic so criminal-geographic testing was developed by kim rossmo
• criminal-geographic testing is more complex and creates a 3D heat map of where offenders base may be, this is called jeopardy surface
• AO3 of geographical profiling

  • canter and larkin (1993) - 87% sexual assaulters were marauders
  • difficult to distinguish if they are a marauder or commuter, also difficult to distinguish crimes committed by different offenders - reduces application
  • bottom up approach is more scientific than top down approach