Bottom-up approach to profiling Flashcards
what did Canter say
profiling should be based on psychological theory and research
interpersonal coherence, forensic awareness, smallest space analysis are the three main features of
investigative psychology
explain interpersonal coherence
we would expect to see coherence between the crime, the offenders behaviour towards the victim and everyday life behaviour
explain forensic awareness
certain behaviours may show the offender is aware of police techniques so an image of where they are may start to emerge e.g. high iQ/been in trouble before so we can narrow down the potential criminals
example of forensic awareness
Davies et al found rapists who conceal fingerprints had a previous burglary conviction
explain smallest space analysis
it is a statistical technique, data about many crime scenes and offenders are correlated to find common connections
example of smallest space analysis
Salfah and Canter analysed murders in the UK where the victim was a stranger and identified 3 underlying themes - instrumental opportunistic (murder used to reach a goal), instrumental cognitive (more planned as don’t want to be caught) expressive impulsive (felt provoked by the victim)
explain geographical profiling
about the location of the crime. people are more likely to commit crimes where they live/tend to travel as it is less effort. it analyses locations of a connected series of crimes and considers the spatial relationships of different crimes and how they relate to the offenders place of residence
what is circle theory
most offenders commit crimes within an imagined circle of a place familiar to them. the more crimes they commit the easier they are to track
what is CGT
criminal geographic targeting. it is a computerised system by Rossmo based on a formula that produces a 3D map displayed spatial data related to time, distance and movement to/from crime scenes
E-validity- more scientific as it uses objective statistical techniques and computer analysis
investigators are able to manipulate geographical, biological and psychological data quickly to produce results that will aid the investigation. the results can be applied to a wider range of crimes
E-validity- smallest space analysis+spatial consistency can be used to investigate crimes such as burglary/theft as well as more serious crimes such as rape/murder
more valid as can be generalised to more crimes but the data tells us little about patterns of behaviour related to unsolved crimes
E-effectiveness- Canter…
collated information from 120 murder cases involving serial killers. smallest space analysis revealed that they had spatial consistency in the behaviour of the killers. the location of each body disposal site was in a different direction of the previous one with the offenders base in the centre. supporting circle theory
E-effectivess- sometimes the offenders base is not in the centre
so the police will commence their searches in the wrong place. but this is useful in house-house searches or identifying geographical areas where DNA could be collected
E2-effectiveness- Copson…
surveyed 48 UK police forces suing the approach and found 75% of the police stated that it was useful. but only 3% said the profile advice helped to identify the offender. profiling can’t identify an offender but can narrow down the potential suspects
