Paper 3 - Forensics Flashcards
Where/by who/when was the top down offender profiling approach made and what is it also known as?
Typology approach is the American approach created by the FBI in the 1970s.
What is the aim of top down profiling and what is top down profiling
Aim : To narrow down a list of suspects to find the perpetrator.
Top Down: American approach to profiling (1970s)
Created by the FBI
Known as typology (a type)
Classification (system) to Data (from crime scene)
Use a classification system, then a behavioural analysis is conducted based on the crime scenes and interviews with the witness/victim.
It’s a best fit model
Based on the idea we gave signature ways of working
Mainly used for murder and rape cases
What are the 4 stages of top down profiling and explain them
Assimilation : Data from crime scene reviewed (pathology report, all evidence, weapon, interviews).
Crime Scene Categories (classification) : Developed from interviews from 36 sexually motivated murderers and their crime scene data (organised or disorganised)
Crime Reconstruction : Hypothesis about behaviour & events of crime created.
Profile Created : Background & physical characteristics of perpetrator written up and given to police.
Top down profiling : crime scene characteristics and likely personality/behaviour of organised and disorganised criminals.
Organised:
Crime scene = evidence of planning, victim is stranger, removes weapons from scene, body hidden
Personality = average-high intelligence, socially/sexually competent, living with a partner
Disorganised:
Crime scene = little evidence of planning, victim is known, leaves evidence at scene (semen/blood), body in open view
Personality = below-average intelligence, socially/sexually incompetent, lives alone and close to scene
A03 : Top Down profiling : + high ecological validity
High Ecological Validity : 36 sexually motivated offenders interviewed, this was considered along with characteristics from the crime scene to develop the classification system. This is high ecological validity.
A03 : Top Down profiling : + Canter
Canter : 10, serial killers were analysed using smallest space analysis to analyse 34 occurrences of serial killings. Found it matched the FBIs typology = valid.
A03 : Top Down profiling : + Meketa
Meketa : Method can now be applied to burglary. This led to an 85% increase in solved crimes. More useful than originally devised to be used for. Burglary in a greater % of crime stats.
A03 : Top Down profiling : - small sample/can’t generalise
Small sample/can’t generalise : Only based in 36 (small sample) sexually motivated (not all crimes are sexually motivated - can’t be generalised) caught offenders.
A03 : Top Down profiling : - self report
Self Report -> reduces reliability : The offenders can like to police as revenge because it is an interview so can easily lie. They can also hold back info so they don’t get further prosecutions. Interviews were not standardised questions so this reduces reliability.
A03 : Top Down profiling : - Goodwin
Goodwin : Serial killers have contrasting characteristics as they don’t just fit into one category. A continuum would be a better method. Therefore the categories aren’t an appropriate method to get the correct category.
What is the bottom up offender profiling method (who by, what does it do and aim)
British approach to profiling
Data -> classification
Uses quantitative data (computer systems)
Suitable for ALL crimes
Can distinguish between multiple offenders in an area
Narrows down a list of suspects to find the perpetrator
Aim : to create a profile of the offender (routines, background, characteristics)
Bottom up approach : explain 2 parts to investigative psychology
1, Statistical analysis : A procedure that detects patterns across crime scenes. It acts as a baseline for comparison
2, Interpersonal coherence : Offender behaviour usually matches everyday behaviour = it is coherent. It reveals information about the offender (I.e. how they relate to men/women)
Bottom up approach : explain geographical profiling (2 models of behaviour & _ theory)
Crime mapping is used to identify the home/base of the offender. Offenders tend to work in areas they know well = spatial consistency.
This is used with psychological theory to create a profile -> modus operandi
2 models of behaviour:
Marauder = operates close to home
Commuter = travels to offend
Circle theory: Patterns of crime are eventually likely to form a circle around the perpetrators base/home. It provides information about their crime making decisions.
A03 : Bottom up profiling : + canter (interpersonal coherence)
Canter - interpersonal coherence : analysed 66 assault cases using smallest space analysis and found several similarities in behaviour. This backs up interpersonal coherence. Would then explain why
A03 : Bottom up profiling : + canter (valid)
Canter - valid : analysed 120 murder cases and found the perpetrators home was usually at the centre of several crime scenes in a circular pattern. Demonstrates circle theory is valid
