Statements about true and false intentions: using the Cognitive Interview to magnify the differences

This study investigates the combined effect of the Cognitive Interview (CI) and the unanticipated questions approach on the magnitude of the elicited cues to true and false intentions. The participants (N = 125) planned for either a mock crime or a non-criminal event, half of them were interviewed with a standard interview (SI) and half with the CI. All participants were asked one set of questions targeting their intentions (anticipated questions) and one set of questions targeting the phase in which they planned their stated intentions (unanticipated questions). As predicted, the questions about the planning phase were perceived as unanticipated by both liars and truth-tellers. Furthermore, and as predicted, the truth-tellers' (vs. the liars') answers to the unanticipated questions were significantly more detailed. Importantly, and in line with our predictions, for the answers given to questions about the planning-phase, liars and truth-tellers differed more clearly in the CI-condition than in the SI-condition, indicating that the CI indeed magnified the differences between liars and truth-tellers. In addition, and as predicted, the truth-tellers' (vs. the liars') descriptions of their intentions were more characterized by information related to how to attain the stated goal.