Forensics: Offender Profiling - Top-Down Flashcards
What is offender profiling?
A tool to help investigators to accurately predict likely offenders.
What are the two approaches to profiling?
Top-Down + Bottom-Up
What is the Top-Down approach?
Starts with theories about the type of offender then theories are applied to crime scene.
-Developed by FBI
What are the two categories in top-down approach?
Organised + disorganised offender
Why was the top-down approach developed?
A way to solve extreme and bizarre cases
What are the 4 stages in the top-down approach?
- Data Assimilation
- Crime Scene Classification
- Crime Reconstruction
- Profile Generation
What is data assimilation?
Data is collected including:
- Crime scene photos
- Background info on victim
- Details of crime
What is crime scene classification?
Profiler starts to make decisions about the data and organises it into meaningful patterns.
E.g. (organised or disorganised) (murder type) (time factors).
What is crime reconstruction?
A profile constructed with hypotheses about what happened during the crime:
- Victim behaviour, crime sequence.
- Aim is to narrow down list of suspects.
What is profile generation?
Unwritten report. Match profile against existing data held.
What study was used for top-down approach?
Douglas and Ressler
What was the aim of Douglas and Ressler?
To identify the major personality characteristics of serious offenders and how they differed from non-offenders.
Who were the participants of Douglas and Ressler?
36 convicted serial killers in American prisons whose crimes had sexual orientation.
What was the method in Douglas and Ressler?
Lengthy unstructured interviews with info collected about crime scenes.
What were the results in Douglas and Ressler?
Info from crime scene revealed that crimes were either premeditated or sudden.
What was concluded from Douglas and Ressler?
Ressler concluded that the crime scene could be used the same way as a fingerprint to help identify murderer. Believed it was clear to decide ‘organised’ or ‘disorganised’ offenders.
AO3 positives on top-down approach?
- Has been used for 40yrs by FBI (temporal validity)
- Copson (1995) : 82% of police offenders said it was useful and 90% said they would use it again.
AO3 negatives of top-down approach?
- Low validity
- Snook (2005)
- Only applies to certain crimes (can’t generalise)
- Douglas and Ressler is based on 36 offenders (male, American) - pop + cult validity.
