Bottom up

• Bottom up approach

  Profilers start with details and evidence collected from the crime scene to develop hypothesis about the likely characteristics , motivations and social background of the criminal.
• where was the bottom up approach developed

  The UK by Canter
• investigative psychology

  Applies statistical procedures alongside psychological theory to the analysis of the crime scene evidence.
• aim of investigative psychology

  Establish patterns of behaviour likely to occur across crime scenes
• what are statistical data bases used for?

  Act as a baseline to which details of the crime and related crimes are added to reveal data about the offender and help link offences.
• interpersonal coherence


  The way in which an offender behaves at the crime scene
• forensic awareness


  Someone who has been the subject of a police investigation before so knows how to evade forensic collection and evidence
• geographical profiling


  The study of spatial behaviour in relation to crime and offenders. Focussing on the location of the crime to give clues about where the offender lives works and socialises
• least effort principle


  If there are two suitable crime areas the criminal will choose the one closest to their base.
• distance decay

  The number of crimes will decrease the further away from the criminals base. There is a buffer zone around their base to decrease their chances of being recognised.
• circle hypothesis

  Because criminals operate according to a limited spatial mindset crimes radiate out from their home base creating a circle. There are 2 types of criminal according to this hypothesis. Marauder and commuter
• marauder


  their base is within the circle of crimes
• Commuter


  their base is outside the circle of crimes as they travel to away to commit crimes
• criminal geographic targeting

  Includes features of the environment to create a 3D 'heat map' of where the offenders base is called a jeopardy surface. Excludes areas such as parks as the home base but includes areas such as a story of flats as a home base
• AO3 bottom up strengths

  + research support - Landrigan and Canter 2001 collated data from 120 serial killer murder cases and used small space analysis to find consistency in their behaviour. Body disposal sights form a circle around their home base , more noticeably in marauders.

  + research support - Canter and Heritage 1990 conducted a small space analysis on 66 sexual assaults. There were several common behaviours such as impersonal language allowing for case linkage as people are consistent in their behaviour.
• AO3 bottom up weaknesses

  x cannot be used alone - Relies on data provided by the witnesses. Yet 75% of crimes go unreported. Profiling also requires other factors such as age , experience and the time of the crime

  x research opposition - Copson 1995 surveyed 48 police departments finding that 83% of information about criminals was judged as useful but only 3% of the information helped the crime to be solved. So information can be misused.