Evaluating Truthfulness and Detecting Deception
DETECTION OF LIES
Nonverbal Examination
Investigators can improve their ability to detect lies by becoming more aware of and skillful in reading the nonverbal cues to lying. In examining such important nonverbal behaviors as gestures, voice, and verbal style, officers first must focus on the facial expressions of emotion, especially those known as micro- and subtle expressions, because these both are involuntary and have demonstrated association with deception.
Microexpressions are fleeting expressions of concealed emotion, sometimes so fast that they happen in the blink of an eye—as fast as one-fifteenth of a second. This results from the individual’s attempt to hide them. They generally go unnoticed in daily social interactions; the most reliable evaluations are done by the review of slow- and stop-motion videotape of the speaker.
However, people can learn to see them in real time. For instance, trainees at the FBI National Academy typically can increase their recognizion of microexpressions to above 70 percent, in some cases over 90 percent; studies on other populations, including U.S. Coast Guard senior investigating officers, have shown average posttraining accuracy of better than 80 percent.These same officers almost doubled their ability to accurately read individuals who displayed these microexpressions in real-world, real-time settings. This ability is retained weeks after initial training.
Facial expressions of emotion, including macro-, micro-, and subtle expressions, are universal and independent of race, culture, ethnicity, nationality, gender, age, religion, or any other demographic variable. All people express emotions on their faces in exactly the same ways. Moreover, they are immediate, automatic, and unconscious reactions. These are incredible characteristics of facial expressions because learning to read them means that someone can have a bigger window into the soul of almost anyone. It is a powerful tool for investigators because facial expressions of emotion are the closest thing humans have to a universal language.