Criminal profiling Flashcards
TOP DOWN (FBI) (Describe how top down typology is used to create a profile) Background
The ‘Top down’ approach is used by the American FBI and was originally based on interviews with 36 convicted serial killers and rapists, combined with insights from many crimes solved by the FBI.
It attempts to classify offenders into types which are based upon the nature of the crime, violence involved and motivations of the offender. Hazelwood and Douglas suggested there a two types of offender typologies: organised or disorganised.
TOP DOWN (FBI) (Describe how top down typology is used to create a profile) Organised and disorganised characteristics
Organised offenders are thought to be above average intelligence, socially and sexually competent and likely to angry or depressed at the time of the crime. Their crimes are clearly planned in advance, with evidence being removed from the scene.
Disorganised offenders are likely to live near the crime, be socially and sexually inept and have below average IQ. The weapon used is likely to be improvised, with little or no effort to remove any evidence, as well as showing a lack of control at the scene.
TOP DOWN (FBI) (Describe how top down typology is used to create a profile) 4 FBI profiling stages
The FBI uses these typologies to create an offender profile in four stages. Firstly data assimilation where info about the crime is gathered from multiple sources. The crime scene is then classified as organised or disorganised. The crime is reconstructed and a hypotheses of what happened during crime are generated. Finally allowing a profile generation including a sketch with demographic and physical characteristics as well as behavioural habits of the offender.
BOTTOM UP (UK)
(Describe the bottom up approach to creating a profile)
Background
Is used in the UK and was developed by David Canter. It looks at details gathered from the crime scene to gradually build up a profile of the criminal and identifies associations between offender characteristics.
BOTTOM UP (UK)
(Describe the bottom up approach to creating a profile)
Criminal consistency hypothesis
An underlying assumption of this approach is the criminal consistency hypothesis, which has two parts; spacial consistency and interpersonal consistency.
Spacial consistency refers to a criminals likelihood to commit crimes in areas in which they are familiar.
Interpersonal consistency refers to a criminals likelihood to commit crimes which reflect their level of social competency.
BOTTOM UP (UK)
(Describe the bottom up approach to creating a profile)
Circle theory
Canters circle theory is based upon the assumption of spacial consistency. His circle theory suggests there are two types of criminals; commuters and marauders. Marauders commit crimes around their home and commuters commit crimes in areas they have commuted to.
BOTTOM UP (UK)
(Describe the bottom up approach to creating a profile)
John Duffy
A famous example of when this approach has been used was the ‘John Duffy Railway Rapist’ case, where a serial rapist was found from a list of 2000 suspects using a criminal profile from the bottom up approach. The profile was formed using details from the crimes and individual characteristics such as, mid 20s, lived in area and knowledge of railway system. This case highlights how the bottom up approach is used to create a successful profile.
CASE STUDY-JOHN DUFFY
(Describe one case study as an approach to criminal profiling)
Background
The bottom up approach to criminal profiling is used in the UK and was developed by David Canter. It looks at details gathered from the crime scene to gradually build up a profile of the criminal and identifies associations between offender characteristics. A case study on John Duffy the ‘Railway Rapist’ uses the bottom up approach.
CASE STUDY-JOHN DUFFY
(Describe one case study as an approach to criminal profiling)
The case
Between 1982 and 1986 24 women were sexually assaulted and 3 murdered at railway stations in London. Canter became interested in the case and with two Police Officers they drew up an offender profile. Canter placed all the cases on a map and this allowed him to speculate about where the rapist might live-circle theory. He categorised perpetrators as ‘marauders’ or ‘commuters’.
CASE STUDY-JOHN DUFFY
(Describe one case study as an approach to criminal profiling)
Preliminary profile
- Considered a marauder.
- Mid to late 20s.
- Marriage problems and no children.
- Probably semi-skilled weekend work or casual labour.
- Likely to keep himself to himself, but has one or two very close male friends.
- Knowledge of railways.
- Keep souvenirs of crime.
- The variety of his sexual actions suggest considerable sexual experience.
- He was probably arrested before for being aggressive and under the influence of drink or drugs.
CASE STUDY-JOHN DUFFY
(Describe one case study as an approach to criminal profiling)
John Duffy’s profile
- Late 20s.
- Separated and infertile.
- Travelling carpenter.
- Only has two friends including David Mulcahy, his accomplice.
- 33 door keys from victims.
- Hard core porn videos found in home.
- Known to police for raping wife at knife point.
CASE STUDY-JOHN DUFFY
(Describe one case study as an approach to criminal profiling)
Conclusion
So by using details of the crime scene combined with geographical profiling Canter developed a bottom up profile for the suspect. He was correct on 13 out of 17 of the characteristics, which allowed John Duffy and accomplice to be caught from 2000 suspects.
