Offender Profiling

• offender profiling: a tool to predict and profile the characteristics of unknown offenders
• top down approach: using a typology (organised/disorganised) to profile offenders
• bottom up approach: using evidence from the crime scene to develop a hypothesis about the offender
• what country typically uses the top down approach?

  america
• what are the four stages to top down offender profiling?

  • data assimilation
  • crime scene classification
  • crime reconstruction
  • profile generation
• what are the two typologies the top down approach proposes to categorise offenders?

  organised and disorganised
• what research supports the top down approach to offender profiling?

  canter - content analysis - third crime committed by each serial killer was analysed using crime classification manual - twice as many disorganised as organised crime scenes were indentified - all crimes had to have an organised element as hadn't been caught after 3 killing
• the top down approach involves the crime scene evidence being reviewed and categorised before a profile is attempted to be produced
• two strengths of the top down approach to offender profiling

  • first approach - prompts discussion
  • successful in 17% cases
• the top down approach to offender profiling is limited because it is based on interview data which may suffer from social desirability bias, potentially damaging the validity of the approach
• limitation of the top down approach

  developed in the 1970s so may lack temporal validity
• why is the top down approach criticised?

  douglas - added a mixed offender typology which has characteristics of both organised and disorganised - not all crimes fit into one typology only
• the bottom up approach is a british approach to offender profiling
• what are the three characteristics of the bottom up approach?

  • interpersonal coherence: how the offender behaved at the crime scene
  • the significance of place and time: where and when was the crime committed
  • criminal characteristics: gives an idea of what type of crime they are dealing with eg is the offender obsessed with control
• research support for the bottom up approach

  copson - profiling only helped to solve a crime in 14% of the cases but it was believed to help to some extent in 83% cases
• geographical profiling: an offenders operational base and possible future offences are revealed by the geographical location of their previous crimes
• what are the two types of offenders in terms of geographical profiling?

  • commuter --> likely to have travelled a distance away from their usual residence
  • marauder --> operates in close proximity to their home base
• circle theory: applied by drawing a circle around crime - the offender is thought to live somewhere inside the circle
• supporting evdience for the bottom up approach (investigative psychology)

  canter et al --> analysis found people are consistent in their behaviour
• supporting evidence for geographical profiling

  in 75% rape cases the offender lived within a 5 mile radius of the offence
• strength of geographical profiling

  practical applications --> directs police to locations
• strength of the bottom up approach

  objective as uses statistical methods --> more reliable
• limitation of the bottom up approach

  geographical profiling may not be sufficient on its own - reliant on quality of data provided