TRAP-18 (Terrorist Radicalization Assessment Protocol)
Definition
An 18-indicator threat assessment framework developed by Meloy and colleagues, comprising 8 proximal warning behaviours (pathway, fixation, identification, novel aggression, energy burst, leakage, last-resort thinking, direct threat) and 10 distal background characteristics; validated retrospectively across jihadist, far-right, and incel lone-actor cases.
- Developer
- Meloy and colleagues
- Structure
- 8 proximal warning behaviours, 10 distal characteristics
- Validation base
- Jihadist, far-right, and incel lone-actor cases
- Type
- Threat assessment framework
Common questions
Why does TRAP-18 cover such different ideological categories in one framework?+
The warning behaviours it tracks, such as fixation or a novel escalation in aggression, tend to appear regardless of the specific ideology driving a person, so the same structured assessment applies whether the case is jihadist, far-right, or incel-motivated.
How is TRAP-18 typically used by a threat assessment team?+
An analyst scores the available information about a subject against the 18 indicators to structure a case discussion and prioritise intervention or monitoring resources, rather than to generate a single numeric risk score.
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- Leakage
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