Investigative tool employed by police, narrows down field of enquiry and suspects. Methods vary but usually involve careful scrutiny of crime scene and analysis of the evidence in order to generate hypotheses about the probable characteristics of the offender.
The Top Down Approach:
- Also known as the American Approach, originated in the US as a result of work carried out by the FBI in the 1970’s
- Based on interviews with 36 sexually-motivated serial killers
- Offender profilers match what they know about a crime to a pre-existing template, classifying the offender as an organised or disorganised offender based on evidence.
Organised Offender:
- Shows evidence of planning and targeting the victim, may have a ‘type’
- High level of control during crime
- Likely to be socially or sexually competent
- Tend to have above-average intelligence
Disorganised Offender:
- Little evidence of planning/impulsive
- Leaves clues behind
- Likely to be socially or sexually incompetent
- Likely to have low intelligence, and be unemployed
Constructing an FBI Profile in 4 main stages:
- Data assimilation – reviewing evidence
- Crime scene classification – organised or disorganised
- Crime reconstruction – hypothesise sequence of events, behaviour of victim, etc
- Profile generation – hypothesis of likely offender, eg: demographic, behaviour, physical appearance
Limited Approach – works best with murder or rape, but reveals little about common offences such as vandalism or burglary because crime scene reveals very little about offender – approach has limited usefulness in finding all criminals.
Based on out-dated models of personality – Alison et al (2002) – this approach is based on models of personality that see behaviour being driven by stable personality traits, whereas nowadays research shows behaviour can also be driven by more fluid external forces which this approach doesn’t consider – this theory has poor validity when explaining the motives and behaviours of criminals.
Opposing Evidence – David Canter et al (2004) – used technique called ‘smallest space analysis’, analysed data from 100 murders in USA, details of each case examined with reference to 39 characteristics of organised and disorganised killers, findings suggested organised but not disorganised type – does not support classification, opposing evidence undermines validity of the classification of offenders.
Simplistic Approach – Grover Godwin (2002) – asks how police would classify a killer with high intelligence who commits a spontaneous murder – the approach is overly-simplistic and therefore cannot accurately classify criminals, too reductionist, not useful in some scenarios.
Insufficient Sample/Research Support – typology approach developed by interviews with 36 killers – sample is small and unrepresentative, not a reliable basis on which to base a whole approach.
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The Bottom-Up Approach:
- Does not use fixed typologies, more data-driven
- Use evidence from crime scene to hypothesise about characteristics of offender
Investigative Psychology:
- Matches details from the crime scene with statistical analysis of typical offender patterns based on psychological theory
- Establishes patterns of behaviours that are likely to occur across crime scenes
- Specific details of an offence or related offences can be matched to reveal important facts about the offender
- Uses concept of ‘interpersonal coherence’ – offenders behaviour at scene may match their behaviour in every day situations, eg: some rapists are more humiliating while some are more apologetic, which may show how they relate to women generally (Dwyer, 2001)
Geographical Profiling:
- First described by Kim Rossmo (1997)
- Uses information to do with location of linked crimes to infer likely operational base, known as crime mapping
- Can be combined with psychological theory to create hypothesis about their thinking, eg: it is likely they will operate in places they are familiar with
- Spatial decision making can provide insight into nature of offence (planned or opportunistic) as well as transport, employment, age, etc
- Circle Theory (Canter and Larkin, 1993)
- MARAUDERS – those who operate close to home base
- COMMUTERS – those who travel away from usual residence
Supporting Evidence for Investigative Psychology – David Canter and Rupert Heritage (1990) – conducted content analysis of 66 sexual assault cases using computer that identifies correlations. Several characteristics identified as common in most cases such as impersonal language or lack of reaction to victim, occur in different patterns in different individuals – leads to understanding of behaviour changes or whether 2 crimes were committed by the same person, shows that investigative psychology is useful in application as shows how statistical techniques can be applied.
Supporting Evidence for Geographical Profiling – Samantha Lundrigan and David Canter (2001) – collated information from 120 murder cases involving US serial killers, smallest space analysis revealed spatial consistency in behaviour of killers, all had ‘centre of gravity’ where base was located – supports validity of approach, and makes it useful for identifying geographical location of killer.
Scientific basis – use of advanced artificial intelligence, manipulation of geographical, biological and psychological data, grounded in evidence – more objective and reliable, less driven on hunches and more likely to produce accurate information (Canter).
Wide application – useful in a varied amount of crimes , such as theft as well as murder and rape. |
Inconsistent Evidence – Gary Copson (1995) – surveyed 48 police forces, advice given by profiler useful in 83% of cases, but only led to accurate identification of offender in 3% – not entirely useful approach, limited usefulness. |