bottom up approach

• Bottom up approach

  • The bottom-up approach starts with specific details and builds up from there
• Bottom up approach in Britain

  • Police in Britain tend to use a bottom-up approach. This approach starts with the criminal's characteristics and develops the profile based on that.
• Interpersonal coherence


  This means that the way a criminal behaves when they are committing a crime will be consistent with how they behave in everyday life.
• Statistical analysis


  • Statistical analysis is used to identify common themes and patterns of behaviour across several crime scenes. This can be used to identify crimes committed by the same person. Because of interpersonal coherence, this data may also provide details about the criminal and narrow down the range of suspects.
• Geographical profiling

  • Geographical profiling uses statistics to work out the offender's rough location

  
  

  • The circle hypothesis says that serial offenders carry out their crimes within a geographical circle, it also predicts the offender's home will be within this circle.
• Canter and Larkin (1993)


  • Canter and Larkin (1993) tested the circle hypothesis by studying the locations of sexual assaults committed by 45 British serial offenders. They found that 39 of the 45 offenders lived within the circle predicted by the circle hypothesis, suggesting it is valid.
• AO3-Supporting evidence

  Canter used bottom-up profiling to develop a profile of the 'Railway Rapist' - responsible for several rapes and murders of women near railway stations in the 1980's. Canter's profile was of a man in his mid-late 20s, with a criminal record, working a semi-skilled job, poor relationships with women, knowledge of the railways, and living near the crime scenes. This profile turned out to closely match the offender, John Duffy.
• AO3-Wider range of application

  Whereas the top-down approach only really works for crimes such as rape and murder, the bottom-up approach has much wider applications e.g. geographical profiling only requires the locations of the crimes, so this bottom-up approach can be applied to basically any type of crime.
• AO3-Conflicting evidence

  Copson (1995) surveyed 184 UK police officers on the use of offender profiles created by trained profilers. Although 83% of the police surveyed said the profiles were 'useful', just 3% of profiles created by trained profilers resulted in identification of the offender. This suggests bottom-up profiles are not particularly useful in practise.