Offender Profiling

• Offender profiling


  Behavioural and analytical tool intended to help investigators accurately predict and profile the characteristics of unknown criminals
• The top-down approach


  Profilers start with a pre-established typology and work down in order to assign offenders to one of two categories based on witness accounts and evidence from the crime scene
• Organised offender


  Offender who shows evidence of planning, targets a specific victim and tends to be socially and sexually competent with high intelligence
• Disorganised offender 


  Offenders who shows little evidence of planning, leaves clues and tends to be socially and sexually incompetent with low intelligence
• Top Down Approach

  • Originated in the USA as a result of the FBIs work in the 1970s
  • Gathered in depth interviews with 36 sexually motivated murderers
  • Categorised data into organised or disorganised crimes
  • The data from a crime scene matched some of the characteristics of one category which then allows you to predict other likely characteristics
• Characteristics of an organised offender

  • Planned crime in advance
  • Maintains a high amount of control
  • Little evidence left behind at the scene
  • High intelligence
  • Socially and sexually competent so may be married and have children
• Characteristics of disorganised offenders

  • Do not plan in advance
  • Spontaneous attacks
  • Little control maintained
  • Low intelligence
  • Socially and sexually incompetent with a history of failed relationships
  • May live alone and be unemployed
• Constructing an FBI profile

  1. Data assimilation- profiler reviews evidence
  2. Crime scene classification- organised or disorganised
  3. Crime reconstruction- hypotheses in terms of sequence of events and behaviour of victim
  4. Profile generation- hypotheses in terms of offender such as background and physical characteristics
• AO3 Top down approach: Research Support

  • Support for a distinct organised category
  • To test organised- disorganised typology Canter conducted an analysis of 100 US murders committed by a different serial killer
  • Smallest space analysis was used where it identifies correlations across different samples of behaviours
  • Analysis found there are features that many serial killers had
  • FBI typology has some validity
• AO3 Top down approach: Hard to distinguish offenders

  • Many studies suggest that organised and disorganised types are not mutually exclusive
  • There are a variety of combinations that occur at a crime scene
  • It is difficult to classify murderers as one or the other as they may have characteristics of both types
  • The organised- disorganised typology may be a spectrum with murderers displaying a variety of characteristics
• AO3 Top down approach: Wider application

  • It can be adapted to other kinds of crimes such as burglary
  • Some suggest that this only applies to specific crimes such as sexually motivated ones
  • But it has been applied to other crimes and there is an 85% rise in solved cases in 3 US states
  • Adds 2 new categories interpersonal (offender knows their victim and steals something important) and opportunistic (generally inexperienced offender)
• AO3 Top down approach: Flawed evidence

  • FBI profiling was developed using interviews with 36 murderers in the US with 25 being serial killers
  • 24 were organised and 12 were disorganised
  • The sample was poor as they did not select a large or random sample
  • There was no standard set of questions so interviews were different and not comparable
• Bottom up approach


  Profilers work from evidence collected from the crime scene. It does not have a fixed typology and starts with details of the crime and works up from there
• Investigative psychology


  A form of bottom up profiling that uses psychological theory and statistics to analyse crime scene evidence and generate a database of criminal behavioural patterns
• Importance of investigative psychology

  • Data driven approach
  • Statistical database which then acts as a baseline for comparison which can help determine if a series of offences are linked together
  • Assumes interpersonal coherence
• What is interpersonal coherence?


  The way the offender behaves at the scene reflects how they would act in everyday life. Some rapists like to maintain control while some are apologetic which may suggest characteristics they show.
• What is forensic awareness?


  Describes individuals who have been subject to police interrogation so their behaviour may suggest they are aware of being able to get away with their crimes
• Smallest space analysis

  • Patterns are identified to see if a series of offences are linked
  • Reveal the relationship between certain types of crime and certain types of people and behaviour
• Geographical Profiling


  A form of bottom up profiling based on the principle of spatial consistency. An offender's operational base and future offences are revealed by the geographical location
• Importance of geographical profiling

  • Assumes serial offenders will restrict their crimes to areas they are familiar with so understanding the spatial pattern of behaviour will help find where the offender is located
  • Can be used to create hypotheses about the killer and to find their way of thinking
• Canter's Circle Theory

  • There are 2 types of offenders
  • Marauder- someone who operates in close proximity to their home base
  • Commuter- someone who is likely to have travelled a distance away from their usual residence
  • The pattern of offending forms a circle and this can give more insight into why the crime was committed
• AO3 Bottom up approach: Evidence for investigative psychology

  • A smallest space analysis of sexual assault cases found several behaviours were identified as common in different samples of behaviour
  • Each individual displayed a characteristic pattern of behaviour which can help establish if multiple offences were committed by the same person
  • This supports the idea offenders are consistent in their behaviour
• AO3 Bottom up approach: Research Support

  • Canter analysed the geographical information from the crime scene and used investigative psychology to find John Duffy (railway rapist)
  • Canter tried to create a profile after using data from a recent crime
  • His detailed profile lead him to arresting Duffy especially after seeing Duffy's criminal history that supported his profile
• AO3 Bottom up approach: Evidence for geographical profiling

  • Information on 120 serial killer cases was collated
  • Smallest space analysis revealed spatial consistency in the behaviour of killers
  • A centre of gravity was found where a circular effect was made around the offenders home base
  • The effect was more noticeable for offenders who travelled short distances
• Rachel Nickell case

  • Brutally stabbed 47 times whilst her 2 year old son watched
  • Police tried to find the offender and a forensic psychologist used an offender profile and was convinced it was a man called Colin Stagg
  • They then tried to trap him to confess his crime
  • The judge dropped the case
  • Later the real criminal committed another murder and many years later he was convicted for his crimes
• Comparison of top down and bottom up approach

  1. Top down is based on the the unreliable data the murderers they interviewed
  2. Bottom up is based on psychological theory which is objective
  3. Top down is based on a limited sample of 36 serial murderers making it hard to generalise to many crimes
  4. Bottom up is based on investigative psychology so can be generalised to many crimes