A03: The Bottom-up approach - offender profiling

• Evaluation of The Bottom-Up Approach A03

  +Research in Support for investigative psychology (Canter & Heritage 1990)

  +Research in Support for geographical profiling (Lundrigan & Canter 2001)

  -Mixed Results (Copson 1995) (Kocsis et al 2002)

  -GP not sufficient on its own (Ainsworth 2001)
• Research Supporting Investigative Psychology - BUA A03

  • Canter & Heritage (1990) conducted content analysis to compare behavioural characteristics identified in the offenders in 66 sexual assault cases (smallest space analysis).
  • Several behaviours were identified in most cases (e.g. using impersonal language).
  • Each individual displayed a pattern of such behaviours, help establish if 2 or more offenders were committed by the same person ('case linkage').
  • Support one of the basic principles of investigative psychology (& the bottom up approach) that people are consistent in their behaviour.
• HOWEVER canter & Heritage - BUA A03

  • However, the database is made up of only SOLVED CRIMES which are likely to be those that were straightforward to link together - a circular argument
  • This suggests that investigative psychology may tell us little about crimes that have few links between them & therefore remain unsolved.
• Research Support for Geographical Profiling - BAU A03

  • Lundrigan & Canter (2001) collated info from 120 murder cases involving serial killers in US.
  • Smallest space analysis show spatial consistency in behaviour of killers. Location of each body disposal site was in different direction from previous sites, creating 'centre of gravity' (leave base in different directions when dumping body)
  • Offenders' base located in centre of pattern (circular effect) - most noticeable for marauders.
  • Supports Canter's claim: spatial info/GP is key factor in finding base of offender helping to identify/catch.
• Mixed Results - BAU A03

  • Copson (1995) surveyed 48 police departments and found that advice provided by a profiler was 'useful' in 83% of cases, which suggests the approach is VALID. The same study revealed that only 3% of cases led to accurate identification - NOT VALID
  • Kocsis et al (2002) found chemistry students produced more accurate profiles than detectives
  • This suggests that offender profiling may actually have little practical value when it comes to solving cases.
• GP not sufficient alone - BAU A03

  • Recording of crime is not always accurate, can vary between police forces & an estimated 75% of crimes are not even reported to police
  • Even if crime data is correct other factors matter e.g. timing of offence, age & experience of the offender (Ainsworth 2001)
  • This suggests that Geographical info alone may not always lead to the successful capture of an offender.