Forensic Psychology
Question: Discuss the top-down approach to offender profiling.
AO1: • Top-down approach --> uses a pre-established typology (based on
6 experience) to work out which of these profiles the criminal fits
into.
- Originated in the USA because of work done by the FBI in the 1970s,
who gathered empirical evidence (characteristics of possible
offenders) from interviews with 36 serial killers. Profilers will
match what is known about the crime and the offender to a pre-
existing template.
- Profile generation (described by Douglas et al in 1986) includes 4
steps: data assimilation, crime scene classification, crime
reconstruction and profile generation.
• General profiles come first, and the specific details come after.
Offenders are classified into one of two categories (organised or
disorganised).
- Organised offenders --> are socially and sexually competent
(usually married with children), showing evidence of planning and
so are unlikely to leave the body or clues at the crime scene.
Usually have a specific ‘type’ of victim and appear to carry out
the attack in a surgical/ controlled manner.
- Disorganised offenders --> are socially and sexually incompetent
(usually alone and unemployed), showing no evidence of planning and
so frequently leave the body and clues at the crime scene. Attacks
appear to be random, with no specific target and more likely to
happen close to their own home or operational base.
AO3: • Good practical applications for this approach
10 - Copson (1995) questioned 184 US police officers. He found 82% said
the technique is useful in matching suspects to a case (by
identifying characteristics associated with the offender and what
was found at the crime scene) and that 90% would use it again. This
approach has good practical applications for the police force,
allowing them to use this method to help solve crime cases. Good
external validity of the theory.
• Reductionist approach
- The technique assumes that offenders can be classified into just
‘organised’ and ‘disorganised’ offenders. Many offenders will have
a mix of both organised and disorganised features in their crimes.
Therefore, this technique doesn’t take this into account and
oversimplifies the complexity of criminal behaviour, trends, and
patterns. Sticking too rigidity to these offender profiles could
ultimately lead to inaccurate profiling.
• Original research had a weak sample
- The FBI who came up with the approach used a restricted sample of
the most dangerous 36 serial killers in the world. The sample is
most likely going to have differences in personality and thinking
compared to a less violent/ threatening offender, which questions
the extent to which results can be generalised to the wider
population. Therefore, the police may not be able to apply the
categorising approach to capture all offenders, limiting its
effectiveness.
• Based on outdated models of personality
- The typology classification system that the top-down approach uses
assumes that offenders have patterns of behaviour that remain
consistent across situations and contexts. Researchers, such as
Alison et al, suggest that this approach is naive and informed by
46
,old fashioned models of personality that see behaviour as being
driven by stable dispositional traits rather than constantly
changing external factors. Therefore, the top-down approach has
poor validity when trying to identify possible suspects or trying
to predict a suspects next move.
47
, Question: Discuss the bottom-up approach to offender profiling.
AO1: • Bottom-up approach --> data-driven, involves a rigorous approach by
6 looking at the details of the crime including characteristics,
behaviours, and social background.
• Investigative psychology --> profiling can be developed according
to psychological theory and research. Developed by David Canter.
- Interpersonal coherence --> look for similarities as offenders deal
with victims in similar ways they deal with people in their normal
life.
- Forensic awareness --> behaviours during a crime can reveal how
they used certain evidence such as a condom, removal of
contaminated items or drugs.
- Smallest space analysis --> data is used to identify the location
of offenders. Salfati and Canter (1999) identified 3 fees:
instrumental opportunistic (crime committed to achieve a goal),
instrumental cognitive (concern about being detected so crime was
planned) and expressive impulsive (uncontrolled crime & in the head
of the moment). Provides analyst with information about offender
mobility, and therefore guide inferences about likely residential
location.
• Geographical profiling --> Canter suggested an offender’s home base
can be revealed by previous crimes in the area. It analyses the
locations to a connected series of crimes and considers where they
were committed, the spatial relationship between each crime scene
and how they may relate to the offender’s home.
- Circle Theory --> developed by Canter which outlines patterns of
offending behaviour from one’s base. ‘Marauders’ commit crimes
closer to home base creating a ‘circle’ boundary around it, whereas
‘commuters’ travel away from their base towards a different area.
- Criminal geographic targeting (CGT) --> used an algorithm to find
common points which can lead to the likely location of the
criminal. Has previously led to the discovery of killers and sex
offenders.
AO3: • Research evidence to support the effectiveness of the model
10 - Lundrigan and Canter (2001) collected details from 120 murder cases
involving serial killers in the USA and examined them by using
‘smallest space analysis’. They found that killers had spatial
consistency in their behaviour, supporting Canter’s idea that
spatial information is a key factor in determining the base of an
offender. This research support gives the model good external
validity, suggesting it’s valid in real life situations.
• Scientific approach
- Based heavily on statistical analysis of data which takes
information from many different sources as possible into account.
The UK approach is more effective at generating more useful,
objective, and scientific profiles than the top-down approach which
involves the profiler making judgements on past experience. This
gives the bottom-up approach a more scientific creditability.
• Conflicting evidence
- Copson surveyed 48 British police forces and found that this model
provided to be useful in around 83% of cases but led to inaccurate
identification of the offender in 3% of cases. This emphasizes that
studies into bottom-up profiling have found mixed results, which
limits its explanatory power as a model to use in offender
profiling.
• Supporting evidence of investigative psychology by Canter
48
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