ABSTRACT
Clinical and research findings relevant to non-verbal behavior have identified an abundance of signs from the deceiver, as reviewed in this chapter, but unremarkable skills for the deception-detector. This is especially true for forensic applications or when compared to verbal measures/signs of faking. Empirical studies and meta-analyses involving several hundred studies of faking indicate that the vast majority of non-verbal deception-detectors have accuracy levels not much better than chance, and that the outcome of deception judgments depends more on the liar’s credibility than any other difference. Still, non-verbal signs can be utilized by examiners as hypotheses for further inquiry. And all behavior, including non-verbal behavior, must be considered in the comprehensive forensic evaluation. The thrust of future research and development in forensic applications will likely focus on linking outcome statements to: (1) reliable and valid psychometric measures of non-verbal faking, as yet undeveloped; (2) standardized verbal measures of deception; and/or (3) biological/neurological measures and markers of faking.
