Sex & Relationships

7 Simple Ways To Spot A Lie

No. 6: Their pupils dilate.

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Experts explain how to tell if someone is lying about cheating.
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Let's take a moment and be grateful for people who lie. Without them, our Netflix queues would practically dry up overnight. We'd never know Ginny or Georgia, the entire cast of 13 Reasons Why, or Virginia de la Mora from The House of Flowers, whose husband lied about an affair for decades. Lying guides our television plot lines and adds cliffhangers to keep us watching. But there’s a big difference between being entertained by characters who lie and being deceived by people in our actual lives.

Feeling like you can’t trust someone — particularly someone you’re in an intimate relationship with — can be the death knell of a couple. If you’re doubting your partner, how can you tell if it’s all in your head, especially if they won’t talk to you about it?

“There’s no one sign of deception that everyone uses,” says Traci Brown, a body language expert and author. “The top thing to understand is that when people lie, they use a different part of their brain, and their body language goes a little bit haywire. Deception is the intersection of body language, tone, and words, so any of those things can change.”

The biggest thing to look for, she says, is a change away from baseline behavior. Here, Brown and five other relationship experts share common behavioral signs that may signify you’ve caught your partner in a lie — even if they'll never admit it.


They're Defensive

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This is probably the most obvious way to tell if your partner is lying: They overreact and get defensive. If you ask a question, even an innocent one, they fly off the handle. "When your partner gets off the phone and you ask, 'Who were you talking to?' and they respond with hostility like, 'Why are you always so nosy?' or 'I can’t believe you don’t trust me,'" something is up, and it's not your imagination," says Anita Chlipala, a Chicago-based marriage and family therapist.

They may take this a step further and turn the tables on you, as if your questions were an act of projecting, and as if you were the liar. This happens all the time, Chlipala says.


They've Lied About Other Things

Looking for patterns of behavior can be difficult. On one hand, you don't want to hold mistakes against them forever, but on the other, it's common for people who are dishonest to be dishonest regularly, because they don't have much respect for the truth. "If you catch your partner in one hurtful lie, chances are that's not the only one," says life coach Kali Rogers.

It's all about context. If your partner lies once about doing the laundry, that's probably not a sign they're a habitual liar. But if they regularly lie about small things, like whether they ate the last of the peanut butter, you might have something to worry about.

"Small lies are not small. Small lies are big lies,” says relationship expert Audrey Hope. “If someone can venture into this territory or stick their toes into a place of untruth, then lying is their ‘thing.’ Their relationship was not built on integrity.”


Their Body and Words Don’t Match

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If you’re concerned your partner is lying — about why they bailed on dinner, or whether they really loved your abhorrent potato salad — try blocking out the specifics of what they’re saying and focus on their unspoken communication.

MoAndra Johnson, a therapist who specializes in relationship conflict, regularly looks at her clients’ body language to get a sense of whether they’re telling the truth. “Non-verbal cues can show if something is not being revealed, or if someone is not being honest,” she says.

Brown recommends looking at their head and feet. “[As] American people, when you nod your head up and down, that means yes, and when you shake your head, that means no. If you ask someone, ‘Were you talking to Sally last night?’ and they nod their head up and down but say no, believe the body first, and take the words with a grain of salt,” she says. “And we have the least control over our feet. Wherever our feet are pointed is where our attention is.” For example, if your partner tells you they want to work things out but their feet are pointed toward the door, they may have already checked themselves out of the conversation, Brown says.


They Put On A Fake Smile

Their smile doesn't seem normal? That can be a sign as well. We’re all guilty of this to some degree: Maybe you’ve given a fake grin to an overly friendly salesperson or a particularly annoying coworker. It’s the same idea. Those fake smiles look different than genuine ones. Why? It's all about the eyes.

A 2012 study from British Columbia found that lying was often accompanied by a fake smile and, because people find it easier to control the bottom half of their face, it usually doesn't extend to their eyes. It's much harder to make our eyes fake it. You might notice the same thing if your partner is lying. They may plaster on a reassuring smile, but their eyes will be telling a different story.


They Touch Their Face

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There’s a lot of research looking into liars: how people lie, why they lie, and what they look like in the act. If you feel like your partner is being untruthful, use this research to your advantage.

According to Anthony DeLorenzo and Dawn Ricci, co-authors of Warning Signs: How to Know if Your Partner Is Cheating-and What to Do About It, people who are lying will often touch or cover their face and mouth. Some researchers think this act is a distancing mechanism between a liar and what they're saying, a way to deal with lingering guilt that may be surfacing. In a way, it makes sense. Many of us fidget with our hair, clothes, or bodies when we feel uncomfortable. And even for someone who lies regularly, it can still be an uncomfortable thing to do.


Their Pupils Dilate

Your pupils get larger when your brain is working hard — like, for example, if you're trying to convince someone of a lie. Pupil control can’t be learned, so it’s a good indication someone’s being untruthful. They may be able to play games with their words or make eye contact, but, again, the eyes don’t lie.

Of course, there could be other reasons your partner's pupils are dilated. Maybe their brain is working on sudoku or a complicated Slack thread. But the bottom line is that your conversations shouldn't feel like work to them. If you're asking simple questions, you should be having a relaxed conversation. So if it seems like your partner is struggling to answer basic questions, their pupils can confirm that.


They Use “Honesty Words”

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If phrases like "Trust me," "Honestly," and "Just to be honest," are common refrains from your partner, it could indicate a bigger problem. According to fraud examiner Pamela Meyer, author of Liespotting: Proven Techniques to Detect Deception, these sorts of phrases can ironically be signs of dishonesty. "When people use these bolstering statements to emphasize their honesty, there’s a good chance they’re hiding something," she writes. "There’s no need to add them if you really are telling the truth."

This type of language is often manipulative. They may say something like, "Honestly, I’ve been struggling lately, but it's nothing to do with us." It sounds like they're opening up to you but doing the opposite. Don’t let the language of honesty masquerade the truth, especially if they exhibit other red flags.


Traci Brown, body language expert and author

Anita Chlipala, LMFT, marriage and family therapist and founder of Relationship Reality 312

Kali Rogers, life coach and founder of Blush Life Coaching

Audrey Hope, addiction therapist and relationship expert

MoAndra Johnson, MFT, therapist

Pamela Meyer, certified fraud examiner and author

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