“…Successful CTA should progress through a number of stages (Clark, Feldon, van Merriënboer, Yates, & Early, 2008; Hoffman, Crandall, & Klein, 2008), proceeding from preparatory steps to knowledge elicitation, data analysis, and, finally, knowledge representation (Yusoff & Salim, 2012). Through consideration of the available CTA knowledge elicitation techniques, it was decided that the critical decision method (CDM) interview protocol would be most suitable to retrospectively examine the tactical decision-making processes of AFOs and SFOs during a previous firearms incident that they considered to be nonroutine.…”