Offender Profiling Flashcards
Definition of top down
Starting from the crime context (bigger picture eg emotional state, level of experience) and drawing conclusions
6 stages of top down offender profiling (Douglas et al)
1 - Profiling Inputs - information on the crime context and background information on the victim
2 - Decision Process Model - summary of the muder type, time and location factors
3 - Crime Assessment - MAIN part profiler decided whether the offender is organised or disorganised
4 - Crime Profile - profiler creates a full profile based on the background victim information, crime context and type of offender (summary of 1-3)
5 - Report Writing - the profiler creates a report of the crime profile and presents to police
6 - Apprehension- once the offender has been arrested the profile is reviewed against the suspect to see how valid it is and evaluate how it could have been improved
Characteristics of an organised offender
Crime scene
- planning
- body hidden
- removes weapon from scene
- use of restraints
- victim is a stranger
Personality
- average to high intelligence
- socially competent
- skilled employment
- sexually competent
Characteristics of a disorganised offender
Crime Scene
- little evidence of planning
- little use of restraint
- leaves evidence
- body in open view
Personality
- below average intelligence
- unskilled employment
- sexually incompetent
- lives alone and close to scene
Evaluation of top down approach to offender profiling PEELS
1 - useful by police - 184 us police officers - 82% said it was useful 90% would use again however Alison et al found judgements were not reliable over 50% rated profile generally/very accurate on a fake profile
2 - generalisability to offending - interviews with 36 of the most dangerous and sexually motivated murderers - used to identify key characteristics that help read a crime scene - unique and rare are smaller crimes however may not be best source of information because sexual murder and can’t be applied to all crimes
3- furthermore major issue - could mislead investigation as there is no science or theory behind it, ambiguous descriptions made to fit any situation
4 - moreover reductionist as it believes there are two categories - organised or disorganised. - Canter found evidence that classification has little basis in reality - analysed 39 aspects of serial killings in murders by 100 US serial killers - found no clear division between organised or disorganised as they were all organised - however Douglas proposed a solution of mixed but there was still no distinction - undermines usefulness of profiling.
Definition of bottom up
Data driven approach that makes use of statistical data on similar crimes that have been committed to make predictions on characteristics of offending
Bottom Up - Investigative Profiling
Canter developed 3 main features of investigative profiling
1 - interpersonal coherence - people are consistent in their behaviour and there will be correlations between the crime and how people behave in every day life
2 forensic awareness - certain behaviour s may reveal an awareness of particular police techniques and past experience (eg rapidity who conceal fingerprints may have previous convictions of burglary)
3 smallest space analysis - statistical technique - Canter looked at 48 crime scenes from 82 stranger murders in the UK. They found various forensic data was related and more common to different types of offenders.
Bottom up - 3 themes found from investigative profiling
- instrumental opportunistic - using murder to obtain something through easy opportunities
- instrumental cognitive - concern over being detected so very planned
- expressive impulsive - uncontrolled, highly emotional and may feel provoked
Bottom up - Geophysical Psychology
Canter proposed that people do not just reveal themselves through crimes but also in the locations that they choose. It makes sense to assume the offender is likely to commit a crime near where they live because it involves the least effort p. They also have a schema of knowledge and experience making them confident.
Bottom up - Geophysical - Circle Theory
Canter and Larkin suggested that a criminals base might be identifiable by looking at the spatial distribution of crime scenes. If crimes are similar in nature are plotted on the map it may be possible to join the points together to form a circle.
This would be true for a marauder whose home base is in the geographical area but there are also commuters who travel to another geographical area.
Bottom up - Geophysical - Criminal Geographical Targeting (CGT)
This is a computerised system that creates a 3D map of likely locations of where the offender may live. This was created by Rossmo and Rosmo. This map is called a jeopardy surface.
Evaluation of Bottom up processing - investigative and geographical
Investigative
- based on forensic data
- offenders with forensic awareness can avoid detection
- 75% of police force found it useful in survey of 48 police forces
- hard to distinguish multiple offenders
Geographical
- offenders with forensic awareness can avoid detection
- ignored undiscovered crimes
- hard to distinguish multiple offenders
- shook et al examined location of 53 serial murderes and 63% of cases killer lived within 6 miles of
