Catching someone in a lie is a sticky situation. But what if you can't tell if they're lying or not?
If you suspect someone's being untruthful, there are a few things you can do to try and sniff out their unsavory behavior - even without a lie detector test.
Pick up on their posture.
Someone who is lying will often show it with their body language. Oftentimes, they will shrink in on themselves, slouching and slumping to subconsciously protect their body while they're deceiving you.
"As a rule, the more someone allows their body to be open the more likely it is that they are being honest. That is because when your body is open you are more physically vulnerable," psychologist John Paul Garrison told INSIDER. "If you observe someone change their body language to close of their body or do behaviors to calm themselves (e.g., touching their face, rubbing their forehead) then it is possible they are lying."
Look them in the eye.
We've all heard the phrase "look me in the eyes" in reference to when someone is lying. But it turns out there is actually a lot of truth to that: Lack of eye contact is one of the first non-verbal signs that someone is being deceitful.
Eye contact is something personal and intimate. If someone is lying, they often want to disengage with you and de-personalize the situation.
Notice the rate of their movement.
Lying people typically want to trick the questioner into thinking they're calmer than they are, so their movements will reflect that.
Oftentimes they will keep their hands at their sides, sit extremely still, speak slowly, and keep their facial movements to a minimum. Because they may be trying to fake an aura of calm, these behaviors can actually be a huge tell that they're lying.
Be warned: This kind of poker-face lying is indicative of a skilled liar, so it can be hard to pick up on.
Pay attention to their story.
Unless they're incredibly skilled at lying, most liars will have inconsistencies in their story.
Did they talk about meeting a different friend before? Did they mention a store that's gone out of business? Did they claim to speak with a person who you know has been out of the country?
If you're suspicious, listen closely to their story. Catching them in a lie may be as easy as questioning one slip-up.
If the person you're accusing of lying is leaning away from you, that could be a tell-tale sign that they're uncomfortable and their body is betraying them and exposing that.
Check to see if the person crosses their legs away from you, turns their back to you, or places their hands on their opposite side from you. You can also pay attention and see if they are leaning towards or pointing their feet towards the exit in a room, Justin Lavelle, chief communications officer for PeopleLooker.com, told INSIDER.
If this happens, increase your body language towards them. See how they respond - people do not like to be exposed to intimacy and close quarters when they're lying.
Take stock of their response.
If you accuse someone of lying or question their story, pay attention to how they respond. An innocent person may be offended and question you, but a guilty party may go much further in their defense of themselves.
"Good liars will often have a quick and smooth response and use tactics that will redirect attention back to you or incite some kind of emotional response in you that can divert attention away from them and the lie," said Manhattan psychologist Joseph Cilona.
You may be able to expect tears, screaming, and accusations against you if this person is actually lying. Push past it to get to the truth if you truly think they're full of it.
Pay attention to how they shake their head.
Your body can betray you so often when lying and even a simple tip of the head can be your doom.
"Former CIA officers take the identification of cues a step further to discover if someone is lying," Lavelle said. "One example mentioned is verbal/non-verbal disconnect if someone is saying 'yes,' but shaking their head no, this is a potential sign of deceit."
Pick up on any differences in their behavior.
If this person is normally boisterous but has suddenly become quiet when confronted, you may have a liar on your hands.
Picking up on some of the differences in their behavior can tip you off as to whether they're telling the truth. Not every tell-tale sign of lying is so clear cut since everyone lies in a different way. This requires some serious attention on your part.
"The key is to establish a base line for an individual’s behavior and then look for deviations from that baseline in direct response to some stimulus," Jerry Smith, a clinical psychologist former federal law enforcement officer, told me. "An individual deviation or two may suggest an emotional or physiological reaction to something, but does not necessarily mean deception. However, a cluster of deviations in direct response (e.g., within 1-5 seconds of the stimuli and within 1-10 seconds of each other) is a strong indicator that there is an attempt to deceive.
Trust your gut.
Sometimes people are really, really good liars and they won't have many tells at all. Still, if your gut tells you they're lying, then that could be all the prompting you need to have a discussion.
"Even if you aren’t able to pinpoint a mismatch between the verbal and non-verbal message, don’t ignore your gut instinct. It is based on something real," communication expert and author Leslie Shore told INSIDER.