According to Dr. Carol Kinsey Goman, a body-language pro and the author of
The Truth About Lies in the Workplace, "many liars, especially the most brazen, may actually overcompensate by making too much eye contact and holding it too long." Ruh-roh. So, if you can't spot a liar based on darting eyes, what do you do?
1. A fake smile.
It’s hard for liars to muster a real smile while deceiving you. Here's how to tell one from the other: Real smiles crinkle the corners of the eyes and change the entire face. Fake smiles involve the mouth only.
2. Unusual response time.
When a lie is planned (and rehearsed), deceivers start their answers more quickly than truth-tellers. If taken by surprise, however, the liar takes longer to respond — since the process of inhibiting the truth and creating a lie takes extra time.
3. Verbal cues.
When lying, a person's vocal tone will rise to a higher pitch. Other verbal cues include rambling, selective wording (in which a person avoids answering the question exactly as asked), stammering, and the use of qualifiers ("To the best of my knowledge..." "I could be wrong, but..."). It's also been noted that liars use fewer contractions: "I did not have sex with that woman..." rather than "I didn't..."
4. Dilated pupils.
One nonverbal signal that is almost impossible to fake is pupil dilation. The larger pupil size that most people experience when telling a lie can be attributed to an increased amount of tension and concentration.
5. Change in blink rate.
A person's blink rate slows down as they decide to lie — and it stays low throughout the telling of the lie. Then, it increases rapidly (sometimes up to eight times the normal rate) after the lie.
6. Foot movements.
When lying, people will often display nervousness and anxiety through increased foot movements. Feet will fidget, shuffle, and wind around each other or around the furniture. They will stretch and curl to relieve tension, or even kick out in a miniaturized attempt to run away.
7. Face touching.
A person’s nose may not grow when they tell a lie, but watch closely and you’ll notice that when someone is about to lie or make an outrageous statement, they’ll often unconsciously rub their nose. (This is most likely because a rush of adrenaline opens the capillaries and legitimately makes their nose itch.) Mouth covering is another common gesture of people who are being untruthful, as is covering the eyes.
When a person believes what they are saying, their gestures and expressions are in alignment with their words. When you see a mismatch — where gestures contradict words — such as a side-to-side head shake accompanying a “yes” or a person frowning and staring at the ground while telling you they are happy, it’s a sign of deceit or at least an inner conflict between what that person is thinking and saying.
9. Changes in gestures.
Often, in an effort not to let their gestures "give away" the lie, deceivers will hold their bodies unnaturally still. But, be careful, because in other instances, especially after being asked a searching question, you may notice liars accelerate pacifying gestures — like biting their lips, rubbing their hands together, fidgeting with jewelry, touching their hair.
These are difficult to catch, but if you ever spot a fleeting expression that contradicts a verbal statement, believe what you see and not what you hear.
Carol Kinsey Goman, PhD, is a leadership communication consultant and body-language coach. She's the leadership blogger for Forbes and author of
The Silent Language of Leaders: How Body Language Can Help — Or Hurt — How You Lead
The Truth About Lies in the Workplace: How to Spot Liars and What to Do about Them.