CANTER ET AL -organised/disorganised theory of ser
Aim: To test the reliablitilty of the top-down typology and applying them to 100 cases.
Procedure: Content analysis of 100 cases, they came from published serial killers and the third crime by each serial killer was analysed.
Results: Twice as many disorganised as organised offenders identified. Suggesting thay they are more common or easier to identify.
Conclusions: Canter concluded that there is some organised elements to all crimes. It would be better to look at personality differences between offenders.
CANTER AND HERITAGE - developments in offender pof
Aim: To identify behaviour similarities between offences.
Procedure: Content analysis carried out on 66 sexual offences. Smallest space analysis was used and presents results visually.
Results: Five aspects were found central to the cases:
1. vaginal intercourse
2. no reaction to the victim
3. impersonal language
4. surprise attack
5. victims clothing disturbed.
Conclusions: This has become known as the five factor theory. These now contribute to all sexual offences. An analysis of these factors can enable police to decide whether an offence has been committed by the same individual.
CANTER - the case of john duffy 'the railway rapi
Aim: To show successful application of bottom up approach to solving a crime.
Procedure: Canter was invited to help police draw up a profile of the railway ******. Canter examined details of the crimes and built up a profile of the offenders personality. He also studied the locations of the crimes building up a geographical profile. He came up with lots of traits he beleived the attacker to have such as small in height having a semi-skilled job and so on.
Results: One suspect John Duffy matched the profile very closely, so he was investigated and was found to be convicted for two murders and fives rapes.
Conclusions: Case study supports the bottom up approach to offender profiling.