It's not always easy to spot a liar. While sometimes a person's words and mannerisms give them away, others tell fibs with disturbing ease. However, experts say there are still certain telltale signs a person is fabricating the truth—most of which are associated with nervousness. You see, when a person lies—whether it's a harmless fabrication or a malicious mistruth—they become stressed. And when that happens, their body language shifts. Here, therapists and body language analysts tell us the key nervous habits that can help you spot a liar. Keep your eyes peeled, and you might avoid hurt feelings, confusion, or worse.
Their eyes are shifty.
A person's eyes can tell you a lot—especially when they're lying.
"When a person lies, the brain goes into overdrive trying to figure out how to get the person through the situation without being caught," says Colleen Wenner, LMHC, MCAP, LPC, founder and clinical director at New Heights Counseling&Consulting. "The eyes are not moving in a straight line but rather darting around as the brain processes information. This is called micro-shifting, and it happens subconsciously in an attempt to avoid detection."
The liar might also direct their eyes away from the person they're talking to.
Their voice changes.
Another involuntary reaction to nervousness that might happen when a person lies is a change in voice. Wenner notes that this is often characterized by an unusual rise or fall in vocal tone.
"Tension in the voice occurs when trying not to get caught—pitch, volume, or both can experience change," she says. "It's also possible to see changes in how a person speaks, such as stuttering, hesitating, or talking too fast."
A person's mouth might also become dry or tense—as if holding back a lie—and you might even notice them breathing more shallowly than usual. All of this is a result of stress caused by lying.
They hide their hands.
If you think someone is fibbing, take a look at their hands—if you can find them.
"Someone who is lying may close their hands into fists, put their hands in their pockets, or cross their arms," says GinaMarie Guarino, LMHC, of Psych Point. "Each of these behaviors indicates tension in the body and can also be an unconscious method of shielding or closing off from another person out of discomfort that the stress of lying causes."
You probably notice that you're prone to fidgeting when you're in a stressful situation, such as making a tight deadline on a work project or waiting to begin an important interview. The same thing happens with lying.
"When people lie, they often have trouble keeping still and may fidget nervously," says Heather Wilson, LCSW, LCADC, CCTP, executive director at Epiphany Wellness. "This could manifest in them tapping their feet, shifting in their seat, or even pacing back and forth."
Again, the behavior is due to them feeling anxious about being caught, Wilson notes.
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They deviate from their baseline.
A nervous habit for one person might be normal behavior for another. That's why it's important to understand how a person usually acts to spot them in a lie better.
"You detect deceit by reading how far from normal someone is—therefore, you need to know what normal is," says Patti Wood, MA, body language expert at The Gold Standard of Body Language Experts. "For example, you might think that all liars pause before they speak and don't make eye contact, but an honest person who is introverted may do that normally. So you need to know if the person is introverted or extroverted and what their particular baseline quirks are."
Any habit that deviates from that—especially in one of the above-listed ways—could be a sign of dishonesty.