We say a lot without realizing it when our faces do the talking: Learn how to decode the hidden meanings of facial expressions and gestures.

The average person touches his or her face about 40 times per hour. Coincidence? Not according to face-reading expert Eric Standop. Every gesture has a hidden meaning— to decode it, we need only take a closer look…

September 2013, New York City: 27-year-old Nicholas Brooks has been convicted of murdering his girlfriend, 33-year-old fashion designer Sylvie Cachay, and sentenced to 25 years in prison. Hotel staff found Cachay’s body in the bathtub of the room in which she had been staying. There was some evidence that pointed to a violent death, but what ultimately got Brooks convicted was his body language—especially of his face— and the movements of his hands…

CCTV footage shows the young man standing in the hallway waiting for the elevator just minutes after his girlfriend had died. He is pacing back and forth, running his fingers through his hair. “It’s a clear sign of extreme insecurity and fear,” says human behavior expert Patti Wood. The perpetrator also wipes his face with his hands twice, rubbing from the center outward. “He is trying to wipe away the guilt and assume a facial expression that looks neutral,” says Wood. Brooks puts his hands on his stomach and doubles over. “He is so disgusted that it makes him sick to his stomach.” He also places his hand on his neck again and again. “He knows what a bad situation he’s gotten himself into. Frustrated, he looks for a way out and thinks about what to do next.” In court, Brooks sits for hours with his hands folded, at times raising them to cover his mouth. “People behaving like this have something to hide—a dark secret that no one should ever find out.” Based on the testimony given by body language experts and medical professionals in addition to their own impressions, the jury concludes that Brooks had strangled and drowned Cachay.

Because the deciphering of facial expressions and physical gestures is so very effective, more and more interrogation specialists are using facial analysis to elicit secrets from their suspects. One of the leading experts in the field of face reading is Eric Standop. Here he explains what the most common gestures reveal, which details matter, and how you can identify what others really think.