Interviewing to Detect Deception: When to Disclose the Evidence?

Research shows that there are few objective cues to deception. However, it may be possible to create such cues by strategic interviewing techniques. Strategic Use of Evidence (SUE) is one such technique. The basic premise of the SUE technique is that liars and truth tellers employ different counter-interrogation strategies, and that the evidence against the suspect can be used to exploit these differences in strategies. This study examined the effect of the timing of evidence disclosure (early vs. late vs. gradual) on verbal cues to deception. We predicted that late disclosure would be most effective in differentiating between liars and truth-tellers, and that cues to deception in the gradual disclosure condition would progressively disappear due to the suspects’ realization that evidence against them exists. That is, we expected that liars in the gradual presentation condition would become more consistent with the evidence over time. A sample of 86 undergraduate students went through a mock-terrorism paradigm (half innocent, half guilty), and were subsequently interviewed using one of three disclosure strategies: early, gradual, and late disclosure. We measured statement-evidence inconsistencies as cues to deception . Results supported our predictions in that cues to deception were most pronounced in the late disclosure condition. Contrary to our expectations, the results suggested that presenting the evidence gradually may put innocent suspects at a higher risk of misclassification as they seem to adopt a strategy that is more similar to guilty suspects.