High-Stakes Lies: Verbal and Nonverbal Cues to Deception in Public Appeals for Help with Missing or Murdered Relatives

Low ecological validity is a common limitation in deception studies. The present study investigated the real-life, high-stakes context of public appeals for help with missing or murdered relatives. Behaviours that discriminated between honest and deceptive appeals included some previously identified in research on high-stakes lies (deceptive appeals contained more equivocal language, gaze aversion, head shaking and speech errors), and a number of previously unidentified behaviours (honest appeals contained more references to norms of emotion/behaviour, more verbal expressions of hope of finding the missing relative alive, more verbal expressions of positive emotion towards the relative, more verbal expressions of concern/pain and an avoidance of brutal language). Case-by-case analyses yielded 78% correct classifications. Implications are discussed with reference to the importance of using ecologically valid data in deception studies, the context specific nature of some deceptive behaviours, and social interactionist, and individual behavioural profile, accounts of cues to deception.