Behavioural Consistency
Definition
The tendency of a serial offender to repeat the same distinctive behaviours across multiple offences; one of the two necessary conditions for linkage inference.
- Applies to
- Serial offending behaviour patterns
- Role
- One of two necessary conditions for linkage inference
- Paired condition
- Behavioural distinctiveness
Common questions
Why is consistency alone not enough to link two offences to one offender?+
A behaviour can be consistent across offences yet still be common among many unrelated offenders, such as using restraints in a sexual assault. Consistency has to be paired with distinctiveness, the behaviour being rare in the wider offender population, before shared possession of it becomes meaningful linkage evidence.
What kind of behaviours tend to show higher consistency across an offender's crimes?+
Modus operandi elements tied to underlying skill, planning, or fantasy, such as method of entry, victim selection criteria, or specific control tactics, tend to recur more reliably than incidental circumstantial details that shift with opportunity, such as time of day or exact location.
Related terms
- Behavioural Distinctiveness
- The property that the consistent behaviours in question are rare enough across unrelated offenders that shared possession of them cannot easily be...
- Linkage Analysis
- The investigative and forensic method of determining whether two or more crimes were committed by the same person, based on the presence...
- Modus Operandi (MO)
- The functional, learned behaviours the offender uses to commit the offence: how to gain entry, control the victim, complete the act, and...
- ROC / AUC Analysis
- Receiver Operating Characteristic / Area Under the Curve analysis; the statistical method used to measure the discriminative accuracy of a linkage system,...
- Signature
- Psychologically expressive behaviours that go beyond what's needed to complete the offence: posing the body, ritual acts, taking trophies, leaving messages. Signature...
- ViCLAS
- Violent Crime Linkage Analysis System; the RCMP-developed database capturing 168 behavioural and physical fields from serious violent crimes in Canada and adopted...