Forensic Psychology - Offender Profiling Flashcards
- Top down approach - Bottom up approach - Geographical
What is the top down approach to offender profiling?
Pre defined criminal profiles from experience and then the offender is placed in the category most fitting.
- Mainly USA
What is the sequence of the top down approach :
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Assimilation of data - gathered and examined
Classified - into one of 2 profiles (org or disorg.)
Reconstruction - of the crime - get a timeline of the crime
Profile - a profile is then generated - fill in details beyond the profiles
Characteristics of an organised offender
- Above average // high intelligence
- Planned crime
- Socially and sexually competent (married w kids maybe)
- Skilled (has a job)
Characteristics of a disorganised offender
- Below average intelligence
- Crime is impulsive w/ little or no plan
- Socially and sexually incompetent
- Unskilled (unemployed)
Strength of the TD approach - supporting evidence
P : there is evidence to support - McCrary and Grant - used approach to develop a profile of man responsible for murderers of several prostitutes in 1980s.
E: Ended up being the profile for Arthur Shawcross - found guilty
L: A strength as it has evidence to show it successfully works and helps keep safe.
Weakness of the TD approach - simplistic
P: It is overly simplistic
E: Just having two diff groups = too simplistic as it is likely many won’t fit in either neatly
E: High IQ person could commit crime in a fit of rage but this is out of character for someone of the ‘organised’ category
L: Sticking to these profiles could lead to a lot of inaccuracy in profiling
Weakness of the TD - Limited applications
P: Only works for some types of crime
E: Murderers have a specific modus operandi that reveal info about their character - for these, the top down is useful
E: However, crimes such as burglary don’t typically reveal any details about the criminal and so other approaches may be more useful
What is the bottom up approach (where is it most commonly used) ??
Starts with the criminal’s characteristics and from there develops the profile based off that
(specifics first then general profile)
UK
What is investigative psychology ?
The use of scientific psychology and psychological theory to solve crimes and identify criminals
What are the two key concepts of investigative psychology ?
- Interpersonal Coherence
- Statistical Analysis
What is interpersonal coherence?
The way in which a person commits a crime will be consistent with how they behave in real life.
i.e if a crime is very aggressive - they are likely to be aggressive as a person in real life
What is statistical analysis?
A technique used to identify common themes and patterns of behaviour across several crime scenes
i.e - how evidence is disposed, specific acts etc
What is geographical profiling ?
The use of statistical analysis to make inferences about the offender’s location
What is the circle hypothesis?
The idea that serial offenders carry out their crimes within a geographical circle
Also predicts the offender’s home will be within this circle
Canter and Larkin - test for circle hypothesis
- tested the hypothesis by studying the locations of sexual assaults committed by 45 Brit offenders.
Found 39 (87%) lives in the circle - increases validity
Marauder model
Commits crimes within a criminal range from their own home
Commuter model
Travels away from their own home to an area and then commits crimes within a criminal range of the area
Strength of Bottom Up approach - supporting evidence
P: Investigative psychology, Canter used the profile to develop one for the Railway Rapist - several rapes and murders in South - East England in 1980s
E: profile - man in mid-late 20s, crim record, semi-skilled job
E: Profile closely matched John Duffy who was found guilty
L: Increases the validity as it clearly does what it is meant to
Another strength of Bottom Up - Wide range of applications
P: The approach has a wide range of applications
E: Top down = particular modus operandi, bottom up = applied to wider range
E: Bottom up can be applied to basically every type of crime
L: Makes it a useful technique
Weakness of the bottom up approach
P: Copson surveyed 184 UK officers on the use of offender profiles created by trained profilers.
E: Although 83% of police surveyed said the profiles were useful , just 3% of profiles created resulted in identification of the offender
L: Suggests it’s not particularly useful in practice
