bottom up

• • Aim of offender profiling is to narrow the field of enquiry and the list of possible suspects in order to generate a hypotheses of the probable characteristics of the offender 
  • The top down approach is used by the American FBI
  • The bottom up approach is used by the UK Met police
• The bottom up approach: 

  • British approach 
  • Unlike the Top down approach this method does not begin with the pre-existing/fixed categories of organise and disorganised. 
  • No initial assumptions are made about the offender 
  • The profile off the offender is data driven and emerges as the investigator delves deeper into the evidence and the information 

   
• bottom up approach - Investigative psychology:

  • Aims to establish patterns of behaviour that are likely to occur or co-exist across crime scenes 
• bottom up approach - Geographical profiling:

   

  Canter's circle theory:

  • A criminal may commit a crime in a familiar area because they know which areas are quiet or busy and they will be familiar with which route is best when escaping the crime scene
  • Marauder= a criminal who operates close to their home base  
  • Commuter = criminal who is likely to have travelled to commit the crime - but the area is still familiar to them
• supporting evidence - bottom-up approach

  for example, the railway rapist case study. David canter assisted the police in solving this crime through geographical profiling and investigative psychology, analysing the locations of each crime and combining this with details of similar past attacks in the database - shows that it is effective in narrowing the field of suspects and solving the crime accurately, which increases the validity of this method to be used and applied in the real world. 
• geographical profiling=

  The study of spatial behaviour in relation to crime and offenders.

  Focuses on the location of crime as clues to where offenders live, work and socialise.