Combining Verbal Veracity Assessment Techniques to Distinguish Truth Tellers from Lie Tellers

• Main Authors: Aldert Vrij, Samantha Mann, Sharon Leal, Ronald P. Fisher
• Format: Article
• Language: English
• Published: Sociedad Española de Psicología Jurídica y Forense 2020-12-01
• Series: European Journal of Psychology Applied to Legal Context
• Subjects: cognitive credibility assessment information gathering; deception; model statement; reverse order; sketching; verifiable sources
• Online Access: https://journals.copmadrid.org/ejpalc/art/ejpalc2021a2
• ISSN: 1889-1861; 1989-4007

Cognitive Credibility Assessment (CCA) is a verbal lie detection tool consisting of several interview techniques. These techniques have been examined separately but never together. Reflecting the dynamic nature of CCA we combined several of the techniques (free recall followed by a model statement, followed by a reverse order instruction, and followed by a sketch instruction). We examined the new information provided after each stage of the interview and also compared the information provided in the initial recall with the information provided after the entire interview. A total of 47 truth tellers and 47 lie tellers went on a mission. Truth tellers were asked to report their mission truthfully, whereas lie tellers were requested to lie about several aspects of the mission. We measured the total units of information (total details) provided in the interview and the number of complications reported. The results indicate that the pre-registered hypothesis (Hypothesis 1) was supported for complications. Truth tellers reported more complications than lie tellers in each stage of the interview and the difference was more pronounced after the entire interview than after the free recall. As a conclusion, CCA was an effective lie detection method when complications were taken into account.