Application of The Terrorist Radicalization Assessment Protocol (TRAP-18) to the case of the Army-Navy recruiting center attacker in Little Rock, Arkansas

We applied the Path to Intended Violence (PTIV; Calhoun & Weston, 2003) model and the TerroristRadicalization Assessment Protocol (TRAP-18; Meloy et al., 2015) to study the case of a lone-actor jihadistwho carried out a fatal shooting at a joint Army-Navy recruiting center in Little Rock, Arkansas, on June 1,2009. The PTIV model examines incidents using six progressive stages: grievance; violent ideation; researchingand planning; preparation; probing and breaching; and, attack (Calhoun & Weston, 2003). The TRAP-18 is astructured professional judgment (SPJ) tool and comprises of 18 behavior-based warning signs for terrorincidents. The findings from the retroactive application of the TRAP-18 in this case show that in the week beforethe attack, the perpetrator exhibited five of the eight proximal warning behaviours and five of the 10 distalwarning behaviors. The retroactive application of the TRAP-18 and PTIV to cases of targeted violence assistwith identifying a timeline of behaviors, which in turn provides insight into pathway to violence and warningsigns that someone may be a threat of violence