Offender profiling: The Bottom-Up Approach

• Bottom-up profiling


  • Doesn't begin with fixed typologies
  • Profile is 'data-driven' and emerges as the investigator engages in deeper + more rigorous scrutiny of the details of the offence
  • Much more grounded in psychological theory than the top-down approach
• Investigative psychology


  Attempt to apply statistical procedures with psychological theory, to the analysis of crime scene evidence
• Investigative psychology


  1. Develop a statistical database which acts as a baseline for comparison

  2. Match specific details of an offence/ related offences against this database to reveal important details about the offender, their personal history, family background, etc

  3. 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
• Rapists


  • Some want to maintain maximum control + humiliate their victims, others are more apologetic
• How the offender relates to women more generally


  May be indicated by their behaviour towards the victim
• Significance of time + place

  A key variable that, as in geographical profiling, may indicate where the offender is living
• Forensic awareness


  Describes those individuals who have been the subject of police interrogation before, their behaviour may denote how mindful they are of 'covering their tracks'
• Geographical profiling


  Uses info about the location of linked crime scenes to make inferences about the likely home/ operational base of an offender - crime mapping + based on the principle of spatial consistency
• Spatial consistency


  Serial offenders will restrict their 'work' to geographical areas they are familiar with, so understanding the spatial pattern of their behaviour provides investigators with a 'centre of gravity' which is likely to induce the offender's base
• Offender types


  • Marauder - operates in close proximity to their home base
  • Commuter - likely to have travelled a distance away from their usual residence
• Spatial decision-making


  Can offer the investigative team important insight into the nature of the offence, i.e whether it was planned/ opportunistic, as well as revealing other important factors about the offender, such as their 'mental maps', mode of transport, employment status, approximate age, etc.