“That which does not kill us makes us stronger.” ― Friedrich Nietzsche

The average American tells a lie one or two times per day. Most of the time, those little fibs are inconsequential. But what if the lie is a big deal? Do you know how to tell when someone is lying to you? To detect lies, it’s helpful to have a good baseline of knowledge about a person in four key areas: facial expressions, body movements, tone of voice and their normal word choices and phrasing when they speak. While changes in these areas could indicate a lie, it’s not 100% definite proof. People react differently when they are simply nervous, such as fidgeting or a cracking voice, even when telling the truth. However, if you’re getting signals in several of these areas, chances are higher that the person is lying to you.


Facial Expressions

One of the first changes in facial expressions you might notice when someone is lying is their eye contact. Liars change their eye contact in one of two distinct ways, they briefly look away while delivering the lie or they stare directly at you while lying. Other facial expressions that indicate deception include pursing the lips, rolling the lips inward as if holding something back, biting or licking the lips more than usual, squinting, excessive blinking and sudden sweating in the T-zone of the face.


Body Movements

Liars tend to use hand gestures after they speak instead of during the statement or conversation. They also tend to gesture with both hands versus one. Other tells include keeping their palms faced away from you, rocking back and forth slightly, shuffling their feet, fidgeting, itching/scratching and cocking their head to the side. The more of these signs you see in someone’s body language, the more likely it is that they are being untruthful.


What They Say

The content of their speech is another giveaway when someone is being untruthful. When lying, people tend to use phrases like “honestly”, “to tell you the truth”, “I’ll be honest with you” and similar phrases. Someone being deceitful will also use the words “um”, “uh” and “like” more frequently than usual. They also tend to slip up when repeating the lie and begin to say something else but correct themselves at the last minute. For example, “No, I didn’t… I did actually, I did let the dog out”.


Tone of Voice

When someone is lying, they tend to speak in a more high-pitched tone of voice. Their voice might also crack while speaking or they might have to clear their throat more than usual. Another change is that people tend to suddenly change the volume of their voice to speak louder when being untruthful.

When you notice several signs from multiple categories, the chances are high that the person you are talking to is being deceptive. While one or two of these signs could be simply due to nervousness, the more signs there are, the more likely it is that you’re dealing with a liar. Private investigators use these same signs when determining whether witnesses, interviewees and even potential clients are being honest or not.