What are the two approaches to profiling?
Top-down: This starts with theories about the type of offender, and then these theories are applied to the crime scene
Bottom up: Starts with evidence from the crime scene, and then scientific and statistical predictions are made based on the evidence from this crime scene and other crimes
What are the 4 stages in the top-down approach (DCCP)
1) Data assimilation: data is collected from the scene
2) Crime scene classification: profiler starts to make decisions and organise information e.g type of offender, murder type, time, location
3) Crime reconstruction: a profile is constructed with hypotheses about what happened during the crime, strategy to catch the offender is also devised
4) Written profile is made, including match profile against existing data held, and sketch of offender
Types of offender (two types)
There are two types of offender: organised and disorganised
Types of offenders (organised)
Characteristics of offence:
- Planned
- Show’s self-control
- Lack of evidence at the scene
- Weapon hidden
- Targeted victim
Characteristics of offender:
- Above average IQ
- Socially and sexually competent
- Anger or depression at the time of the event
- Skilled occupation
Post-offence behaviour:
- Returns to crime scene
- Volunteers information
Types of offenders (disorganised)
Characteristics of offence:
- Unplanned
- Likely to leave evidence behind
- Victim randomly selected
- Minimum use of contract
- Disorganised behaviour
Characteristics of offender:
- Lives alone, near the crime scene
- Socially and sexually inadequate
- Physically or sexually abused in childhood
- Frightened/ confused at the time of the offence
- Low intelligence/no occupation
Post-offence behaviour:
- Returns to the crime scene to relive the offence
- Keep diary
- Keep news articles of the event
Canter et al (2004)- research support and against top down approach
Evaluation of top-down approach
Origins of the types of offenders
What are the 2 key elements in bottom-up approach
Geographical profiling identifies 2 types of offenders
Evaluation of bottom-up approach
Copson et al (1995)- mixed results for profiling