Bottom up Approach

• The Bottom-up Approach

  • Profilers work up from evidence collected at the crime scene to develop hypotheses about the likely characteristics of the offender
  • Make inferences from systematic analysis of evidence at crime scene
  • Use knowledge of psychological theories & statistical analysis
• Investigative Psychology

  • Form of bottom-up profiling developed by Canter
  • Matches details from the crime w/statistical analysis of typical offender behaviour patterns based on psychological theory
  • Interpersonal coherence - how offender’s behaviour at the crime scene reflects their actions in everyday life, some rapists may seek control of their victims Behaviour can give police insights into how the offender relates to others
  • Significance of time & place
  • Forensic awareness – focuses on individuals who may have been the subject of police interrogation before
  • Statistical procedures applied
• Investigative Psychology - Eval

  Canter and Heritage conducted a contact analysis of sexual assault cases.

  • Data then examined using the statistical technique.
  • Characteristics identified as common in most cases E.g use of impersonal language.
  • This can lead to an understanding of how an offender's behaviour may change over a series of offences.

  + Supports usefulness of investigative psychology & shows how statistical techniques can be applied.
• Geographical Profiling

  • Form of bottom-up profiling
  • Based on the principle of spatial consistency: that an offender’s operational base and possible future offences are revealed by the geographical location of their previous crimes.
  • This is known as crime mapping
• Circle theory

  • Proposes two models of offender behaviour.
  • People operate within a limited spatial mindset that creates imagined boundaries in which crimes are likely to be committed
  • The Marauder: the offender operates in close proximity to their home base.
  • The Commuters: the offender is likely to have travelled a distance away from their usual residence.

  
• Geographical profiling- Has supporting Evidence

  Canter gathered information from 120 Murder cases.

  • Spatial consistency in the behaviour of killers.
  • Location of which each body was disposed created a centre of gravity, offender base was located in the centre of gravity.

  + Supports Canter's claim that spatial information is a key factor in determining an offenders base.
• Geographical profiling Eval - Real Life Appl.

  Canter assisted police in John Duffy's capture (Railway Rapist)

  • Duffy carried out 3 murders and 24 sexual assaults on women near railway stations in north London.
  • Canter analysed geographical crime scene data and combined it with details of similar attacks (interpersonal coherence) to draw up a profile of Duffy
  • Helped lead to his arrest and conviction.
  • Also supports investigative psychology.
  • Specific details of events are matched in a database to determine if a series of offences are linked to the same offender. Canter saw links
• Geographical profiling
Eval - Arguably more objective


  • Arguably more objective and scientific than the top down approach - grounded in psychological theory and evidence and less driven by speculation and hunches
  • It is more systematic and support its utility in the judicial process.
  • We can be confident when drawing conclusions
• Geographical profiling - High Applicability

  • Can be applied to a wide range of offences - statistical analysis, principle of spatial consistency can be used to investigate crimes such as burglary and theft as well as more serious crimes such as murder or rape.
  • Means that the bottom approach is more applicable than its US rival the top down approach.