Forensic Credibility Assessment : A Journal of Science and Field Practice

Purpose The Bogus Pipeline effect refers to a procedure in which individuals are made to believe that their responses to questions will be independently verified by an infallible lie detector, resulting in an associated reduction in socially desirable responses. Polygraph testing is known to elicit increased disclosure by examinees, which some critics claim is an example of this effect. We explored whether a bogus lie detector said to have just 75% accuracy (a level below that of polygraph testing) would be as effective in eliciting disclosures as a 100% accurate lie detector when participants were questioned about cheating in a competition. Method Participants took part in tasks as part of a group, with the winning group receiving £500 to donate to a charity. Each group contained a confederate who cheated on one of the tasks. Participant later returned for a debrief, during which they were asked about cheating within the group. Each was randomized to one of three conditions: one in which they were questioned with the aid of an apparatus they were told was a nearly 100% accurate lie detector, one with a 75% accurate ‘lie detector’ was used, and a control condition. Results A significantly larger proportion of participants in both bogus lie detector conditions than in the control condition disclosed cheating by a group member, but there was no significant difference between the two bogus pipeline groups. Conclusion The bogus pipeline effect may not be bogus after all.