Bottom-Up A01

• Aims of the bottom-up approach


  Generate a picture of the offender: their likely characteristics, routines, behaviours and social background. This happens through systematic analysis of evidence at crime scene.
• Hypotheses


  Unlike TDA, bottom up does not begin with a fixed hypothesis. Instead, a data driven profile emerges as the investigator engages in deeper detail of offence as this approach is more grounded in psychological theory than TDA.
• Investigative psychology


  Attempts to apply statistical procedures, alongside psychological theory, to the analysis of crime scene evidence.
• Aim of investigative psychology


  To establish patterns of behaviour that are likely to occur across crime scenes in order to develop a statistical database which then acts as a baseline for comparison.
• Specific details


  An offence, or related offences, can then be matched against this database to reveal important details about the offender. This may also determine whether a series of offences are linked in that they are likely to have been committed by the same person.
• Interpersonal coherence


  The way an offender behaves at the scene, including how they 'interact' with the victim, may reflect their behaviour in more everyday situations.
• Geographical profiling


  Spatial consistency: that an offender's operational base and possible future offences are revealed by the geographical location of their previous crimes. Time and and place are key variables.
• Rossmo 


  Introduced geographical profiling and used information to do with location of linked crime scenes to make inferences about the likely home base of an offender. This is crime mapping.
• Crime mapping and psychology


  Can be used in conjunction to create a hypothesis about how the offender thinks as well as their modus operandi. Assumption that serial offenders will restrict their work to geographical area they're familiar with.
• Centre of gravity


  Likely includes base of operations of offender. Also helps to make an educated guess where they strike next- jeopardy surface.
• Canter's circle theory


  Proposed two models of behaviour: Marauder (works close to home) and Commuter (travels away). The pattern of offending is likely to form a circle around their usual residence, and this becomes more apparent the more offences there are.