Based on the autonomic nervous system (ANS) study by klein Selle, Verschuere, Kindt, Meijer, & Ben Shakhar (2016), 15 participants pretended to perform a crime shown on a video, which 16 other participants pretended to witness. Both groups then experienced a P300‐based Concealed Information Test (CIT) protocol called the complex trial protocol. Both groups showed CIT effects, with a larger probe than irrelevant P300s at Pz. However, this effect was significantly larger in the suspect group. In contrast, only the suspect group showed delayed N200/N300 responses at F3—putative inhibitory signs. This supports the klein Selle et al. (2016) ANS study in that the suspect versus witness role‐playing manipulation differentially affected inhibitory (vs. orienting) aspects of the CIT situation. Our results are also consistent with Ambach, Stark, Peper, & Vaitl (2008), who saw the same autonomic response fractionation as klein Selle et al., but using Furedy's differentiation of deception method (Furedy, Davis, & Gurevich, 1988). These similarities are discussed.