Offender Profiling: Bottom-up approach Flashcards
steps of bottom up profiling
- analysis of the crime evidence
- psychological theory and stats analysis
- creation of hypothesis of the probable characteristics of the offender
who created Bottom-up profiling
David Canter, used this method to help police catch the ‘railway killer’ John duffy
bottom-up profiling overview
- data driven
- profile made by making inferences from stats analysis of evidence at scene
- use knowledge of psych theories and stats analysis
Investigative psychology
- interpersonal coherence
- smallest space analysis
- forensic awareness
interpersonal coherence
- assume offenders behaviour remains the same whilst committing the crime
- can learn who they are by how they interact with their victim
smallest space analysis
- stats analysis of crime scene evidence from many cases
- database built, enables police to find common patterns which provides offender characteristics
offender charcateristics
- types of offenders
- significance of time and place (crime committed local to the offender)
- how experienced the offender is
forensic awareness
- offenders knowledge of the criminal justice sys and potential previous subject of the police can provide info about who they are
Geographical profiling
- developed by rosmo (97)- criminal geographical targeting
- based on the study of spatial behaviour
- an offenders operational base and future offences are linked
crime mapping
- used to link local crime stats, local transport, and the geographical spread
- make inferences about the likely home or operational base, workplace, and social hangouts of the offender
- assume the serial killer will restrict their ‘work’ to areas they’re familiar with
circle theory
- people operate within a limited spatial mindset
- creates imagined boundaries in which crimes are likely to be committed
circle theory diagram
- offenders home
- buffer zone- no hunting, too close to home
- hunting ‘comfort zone’, offender feels comfortable committing crimes
- distance decay- too far from home, risk and cost too high to travel
the marauder
the offender operates in close proximity to their home base
the commuter
the offender is likely to have travelled a distance away from their usual residence
strengths of bottom up approach
BETTER THAN TDA
- more objective as using biogeographical and psychological data rather than speculation and hunches
- more systematic, supports its utility in all aspects of judicial process
RESEARCH SUPPORT
- Copson: 75% x 48 police forces using investigative psych said profilers advice is useful but only 3% said it helped identify the offender
- may not be useful in catching the offender but slight benefit makes it worthwhile
EVIDENCE TO SUPPORT GEOG PROF
- lundrigan and canter: got info from 120 murder cases stats analysis revealed spatial consistency in the killers behaviours