Lying through omitting information: examining the effect of a Model Statement interview protocol on verbal cues to deceit

Background/objectives: Practitioners frequently inform us that lying through omitting information is relevant to them, yet this topic has been largely ignored by verbal lie detection researchers.

Method: In the present experiment participants watched a video recording of a secret meeting between three people. Truth tellers were instructed to recall the meeting truthfully, and lie tellers were instructed to pretend that one person (John) was not there. Participants were or were not exposed to a Model Statement during the interview. The dependent variables were ‘total details’ and ‘complications’.

Results: Truth tellers reported more complications than lie tellers but lie tellers reported more details than truth tellers. The Model Statement resulted in more complications and details being reported. The Veracity X Model Statement interaction effect was not significant. In terms of self-reported strategies, the main veracity difference was that truth tellers were more inclined to ‘be detailed' than lie tellers.

Discussion: We discuss the atypical finding (most details reported by lie tellers) and ideas for future research.