Top-Down Approach

The Top-Down Approach

Constructing an FBI Profile

Offender Profiling

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• Investigative tool by police when solving crimes.
• Aim to narrow the field of enquiry and the list of likely suspects.
• The compiling of a profile usually involves careful scrutiny of the crime scene and analysis of the evidence, like witness reports.
• Generate hypotheses about the probable characteristics of the offender.

Four main stages in the construction of an FBI profile -

• Data assimilation - profiler reviews evidence
• Crime scene classification - either organised or disorganised
• Crime reconstruction - hypotheses in terms of sequence of events, behaviour of victims, etc.
• Profile generation - hypotheses related to the likely offender

The American Approach

• Originated in the US as a result of work carried out by the FBI in the 1970's.
• Also known as the typology approach.
• Offender profilers match what is known about the crime and the offender to a pre-existing template that the FBI developed.
• Offenders are classified in one of two categories - organised or disorganised.

Evaluation

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Organised Offender

• Best suited to crime scenes that reveal important details about the suspect.
• Also crimes that involve gruesome practices like sadistic torture, dissection of the body, etc.
• More common offences like burglary and destruction of property do not lend themselves to profiling because the crime scene reveals little about the offender.
• Means this is a limited approach to identifying a criminal.

• Canter analysed data from 100 murders in the USA using a technique called smallest space analysis.
• Details of each case were examined with reference to 39 characteristics thought to be typical of organised and disorganised killers.
• Findings suggest evidence of a distinct organised type, but not for disorganised.
• This undermines the classification system as a whole.

• The typology classification system is based on the assumption that offenders have patterns of behaviour and motivations that remain consistent across situations.
• Several critics have suggested this is naive.
• Informed by old-fashioned models of personality which see behaviour driven by stable dispositional traits rather than external factors.
• This approach, based on 'static' models of personality, is likely to have poor validity.

• Show evidence of having planned the crime in advance.
• Victim is deliberately targeted.
• Killer or rapist often has a 'type'.
• Maintain a high degree of control during the crime.
• Little evidence or clues left behind at the scene.
• Tend to be of above-average intelligence.
• In a skilled, professional occupation.
• Socially and sexually competent.
• Usually married and may have children.

Only Applies to Particular Crimes

Evidence Does Not Support Disorganised Offender

Based On Outdated Models of Personality

Disorganised Offender

• Behaviours that describe each of the organised and disorganised types are not mutually exclusive.
• A variety of combinations could occur in any given murder scene.
• Godwin, for example, asked how police investigators would classify a killer with high intelligence and sexual competence who commits a spontaneous murder with the body left at the scene.
• This prompted other researchers to propose more detailed typological models.
• Holmes suggests there are four types of serial killer: visionary, mission, hedonistic and power.
• Keppel and Walter focus more on the different motivations killers might have.

• Typology approach was developed using interviews with 36 killers in the US.
• 25 were serial killers, the other being single or double murderers.
• Critics point out this is too small and unrepresentative a sample.
• Cannot be used as a basis of a system that may have significant influence on the nature of the police investigation.
• Canter argued that it is not sensible to rely of self-report data with convicted killers.

Original Sample

Classification Is Too Simplistic

• Show little evidence of having planned the crime in advance.
• Crime scene reflects the impulsive nature of the attack.
• Body usually left at the scene.
• Very little control on the part of the offender.
• Lower than average IQ.
• In unskilled work or unemployed
• History of sexual dysfunction and failed relationships.
• Tend to live alone and relatively close to where the offence took place.