‘Have no fear of perfection - you’ll never reach it.’ –Salvador Dalí
While interviewing the suspect who claims ignorance about an incident, the witness who saw it happen, or the informant who identified the perpetrator, the detective asks a question that will eviscerate the perpetrator’s story. As the suspect prepares to answer, he looks up and to the left, purses his lips, tenses his eyelids, and brings his eyebrows down.
The investigator knows that a suspect displaying shifty eyes and gaze aversion and looking up and to the left when answering uncomfortable questions is exhibiting signs of lying. The suspect is not totally disinterested, but he is reluctant to participate in the interview. Because the suspect’s behavior suggests dishonesty, the detective prepares to drill still deeper in the questioning.
Unfortunately, this investigator likely would be wrong. Twenty-three out of 24 peer-reviewed studies published in scientific journals reporting experiments on eye behavior as an indicator of lying have rejected this hypothesis. No scientific evidence exists to suggest that eye behavior or gaze aversion can gauge truthfulness reliably.
Some people say that gaze aversion is the sure sign of lying, others that fidgety feet or hands are the key indicators. Still others believe that analysis of voice stress or body posture provides benchmarks. Research has tested all of these indicators and found them only weakly associated with deception. […]
Lies can be betrayed in verbal and nonverbal leakage independently. However, the authors have chosen to further examine this area, analyzing the combined contribution of verbal and nonverbal leakage to the prediction of deception or truthfulness.
