Bottom Up profiling Flashcards
What hypothesis did Canter develop?
- Criminal consistency hypothesis
- States that an offender’s behaviour while committing a crime will be consistent with their behaviour in their everyday life.
- Contains Interpersonal consistency and Spatial consistency
What is interpersonal consistency?
The theory that the behaviour of the offender at the time of the crime will be similar to everyday life.
For example, ‘overkill’ indicates a perpetrator of a violent, sexual crime is likely to be on record for domestic violence.
What is spatial consistency?
Locates the most probable location of the home of the offender from the distribution of the scenes of the crime.
It assumes criminal offences will occur in places the offender makes regular use of.
What is distance decay?
The further from the home of the offender, the fewer crimes.
What is circle hypothesis?
The majority of offender’s homes can be located within a circle, with its diameter defined by the distance between the offender’s two furthermost crimes.
What is the Marauder model?
The offender operates in close proximity to their home base.
What is the commuter model?
The offender travels from home base to a location, eg. workplace, partner’s home, and operates in a circle pattern there.
What is dragnet?
A computer package, based on Canter’s empirical research into the spatial behaviour of offenders.
It uses a series of crime locations and determines the most likely area for the perpetrator’s home.
Who is John Duffy?
- The ‘Railway Rapist’
- 24 sexual attacks and 3 murders in the 1980s, around railway stations across North London.
What from Canter’s profile turned out to be correct?
- Canter suggested he lived in an area near to the area of his first crimes; Duffy did live in the area he suggested.
- Canter said he had a knowledge of railways; Duffy worked for British Rail.
- Canter said he had previous criminal record for violence; Duffy raped his wife at knifepoint.
What are the strengths of Bottom-Up Offender Profiling?
- Case of John Duffy supports the method; led to the capture of Duffy.
- Evidence supports geographical profiling as effective: analysis of 120 serial murder cases was conducted and found evidence for spatial consistency in the behaviour of the killers. The offender’s base was inevitably located in the centre of the circle created by their crimes. However, this is only really useful for serial crimes.
