bottom up

• Bottom up


  Investigative psychology approach to offender profiling that uses statistical data on crimes committed to build a profile, rather than relying on pre-existing typologies
• Investigative psychology


  A branch of applied psychology that focuses on understanding and profiling criminals to assist with solving crimes and provide empirical evidence for court cases
• Geographical profiling


  A field of investigative psychology that involves generalising from the locations of linked crime scenes to the likely home/work/social base of the offender
• Top down approach to offender profiling


  1. Profiler uses experience to create a profile for the crime scene based on typologies

  2. Crime scene analysis

  3. Crime scene -> Draw conclusions
• Organised offender


  Offender whose behaviour at the crime scene suggests they are methodical and controlled
• Disorganised offender


  Offender whose behaviour at the crime scene suggests they are impulsive and chaotic
• Offender profiling in Britain began some years after the Americans had practiced it
• Bottom up approach


  • More scientific as it uses psychological theories and methodologies
  • Attempts to look for ways in which the crime might mirror the behaviour of the offender in everyday life (the criminal consistency hypothesis)
  • Avoids typologies and categorising offenders, arguing it is important to treat each offender as unique and individual
• Interpersonal consistency


  The idea that an offender's interactions with their victim may provide clues about how that person interacts with people in everyday life
• The type of victim may also reflect the sub-group to which the criminal belongs, e.g. Ted Bundy killing over 30 students when he himself was a student
• Forensic awareness


  Offenders who show an awareness of forensic investigation, e.g. by cleaning the crime scene, will probably have committed a crime before and been through the criminal justice system
• Spatial consistency


  The idea that serial offenders operate in a limited area, based on the offender's mental maps and factors like escape routes, presence of CCTV and access to victims
• Circle theory


  The proposal that most of the time, if a circle is drawn that encompasses a series of linked crimes, the offender will be based somewhere within the circle
• Marauder


  An offender who operates in close proximity to their home base
• Commuter


  An offender who is likely to have travelled a distance away from their usual residence
• Canter and Heritage conducted a content analysis of 65 sexual assaults and identified several characteristics common in most cases, such as impersonal language and lack of reaction to the victim
• Lundrigan and Canter's study of 120 murder cases with serial killers in the USA revealed spatial consistency in the behaviour of the killers, with the location of each body disposal site in a different direction from the previous, creating a center of gravity with the offender's base in the center
• Copson's survey of 8 police forces found that the advice provided by profilers was judged to be useful in 83% of cases, but in only 14% did it lead to accurate identification of the offender
• Kocis et al found that chemistry students produced a more accurate offender profile on a solved murder case than senior detectives, suggesting a lack of usefulness and reliability of profiling
• Bottom up approach to offender profiling


  Gathers information then builds a logical description based on that, avoiding typologies and categorising offenders
• Top down approach to offender profiling


  Profiler uses experience to create a profile for the crime scene based on typologies of organised and disorganised offenders