Sender credibility and deception detection

• We investigated the relationships between credibility and deception detection success.
• Participants communicated either through voice-over-IP (VOIP) or by e-mail.
• Deception detection was worse when deceivers were seen as credible.
• Untrained and unmotivated deception detectors found deceivers to be credible.
• VOIP users were more likely to find deceivers credible than were e-mail users.

Recent research has demonstrated that the most important determinant of deception detection success was the perceived credibility of the sender. If so, then what accounts for differences in perceived sender credibility, especially when communication is conducted solely via computer-mediated communication modes where sender and receiver cannot see each other? We investigated the relationships between credibility, its antecedents, deception detection success, and the generation of false alarms. We conducted an experiment involving 74 pairs of undergraduate students. We found that the perceived credibility of the sender significantly affected both detection success and false alarms, such that the less credible the sender, the better the detection and the more false alarms generated. We also found significant relationships between three of the four antecedents and credibility: participants who were trained to detect cues to deception, who were motivated to find deception, and who communicated via e-mail were more likely to perceive senders as not credible, compared to participants who were not trained, not motivated, and who communicated via VOIP. Our findings have implications for both research and practice.