9 Signs Someone Is Lying to You That a Good Liar Can't Hide

Sharing is caring!

Lying has been part of our behavior since we were very young. As children, we quickly figure out that a lie can save us from punishment or get us what we want – and from that point on, this skill only becomes more refined. As adults, we no longer lie because we broke a vase. We lie to avoid conflict, to protect our reputation, to hide an unpleasant truth, or simply because it is easier than explaining ourselves. And here comes the interesting part – researchers from the University of Massachusetts found that the average person lies at least once or twice a day, often even to strangers, within the first ten minutes of a conversation. So no, it is not true that you only encounter lies occasionally. You encounter them all the time; you just do not know how to recognize them.

That is why today I am going to take a detailed look at the signs someone is lying to you – by the time you finish reading, you will be much better at recognizing lies than you were before.

Why Do People Lie in the First Place?

Lying is actually built into our development. Children as young as two already know how to deceive intentionally, and by the age of four or five, they develop what psychologists call theory of mind – the ability to understand that someone else knows less than you do and to use that knowledge to their own advantage. Interestingly, a 2021 meta-analysis involving nearly 7,826 children from 14 different cultures confirms a clear connection: the more cognitively developed a child is, the earlier and better they are able to lie. So lying is not a sign of a bad character; it is a sign of a developing brain.

And this ability does not disappear with age; it simply becomes more sophisticated. Psychologist Bella DePaulo and her colleague Deborah Kashy conducted one of the most frequently cited studies on the subject – nearly 150 people recorded every lie they told that day every evening for a week, including the smallest ones. The finding was clear: people lie in roughly every third to fifth social interaction, and they lie about twice as often for themselves as they do for others. So most lies are about self-protection – avoiding punishment, shame, or an uncomfortable conversation, or trying to appear better than we actually believe we are. A smaller, but still important, portion of lies are prosocial, meaning they are intended to protect someone else – you tell a friend that they did a great job making the cake even though it was not very good, because at that moment you do not care about the truth; you care about how they feel.

Why do we have this ability in the first place? Evolutionary psychologists explain that lying emerged with language itself – once we developed the ability to talk about things that another person could not see, know, or experience, we also gained a tool that could be used to our own advantage. So the same mechanism that allows us to cooperate, tell stories, and pass on knowledge also allows us to deceive. Lies and truth emerged from the same source; one serves connection, while the other serves survival.

9 Signs Someone Is Lying to You

1. Subtle Changes in the Face

The face is often the first thing to give someone away when they are lying. Slight blushing, flared nostrils, faster blinking, biting the lips, looking away, confusion – all of these are micro-reactions that occur because lying triggers a stress response in the body. Our brains are working harder as they construct a convincing answer or story, so that effort has to show somewhere.

Researchers have also identified some specific signs that are fairly reliable. Pupils often dilate when someone is lying because this is an autonomic bodily response that is almost impossible to control. A smile becomes “flat” – you see only the movement of the lips, while the eyes remain still, without the tiny wrinkles at the sides that appear during a genuine smile. And the lips themselves can reveal a lot – liars often press their lips together, making their smile or expression look forced and tense.

2. Changes in Voice Tone and Speech Structure

When someone is lying, not only what they say but also how they speak often changes. Their speaking speed may shift in either direction, the pitch of their voice may rise or fall, and their sentences may become unusually complex. That last point is interesting – you might expect a liar to speak more simply, but in reality, the opposite often happens because the brain tries to further “support” the story with more details and a more polished sentence.

In addition, unusual pauses, stumbling, and vocal “breaks” in the middle of a sentence often appear. This can be a sign that the brain is still constructing the answer at that moment instead of simply retrieving it from memory.

3. The Body Shrinks

When people lie, they often unconsciously “make themselves smaller” – they pull their arms closer to their bodies, hunch their shoulders, and become less relaxed in their posture. Forensic experts refer to this as “minimizing,” and it is an old survival response: the less space you take up, the less noticeable you are, and the body does this automatically when it feels threatened by the lie the person has just told.

There is also an interesting study by the well-known zoologist Desmond Morris, in which he asked nurses to lie to patients about their medical condition as part of a role-playing exercise. Those who lied touched their faces much more frequently than those who told the truth. In addition, observe whether a person suddenly “puts up a barrier” between the two of you during a conversation – a cup, a phone, or their hand on the table. This is an unconscious attempt to physically protect themselves when they have nowhere to escape.

4. Suddenly Redirecting the Conversation

If you notice that someone suddenly steers the conversation away from the topic you have just brought up, this is a known sign of lying. Redirecting attention is one of the oldest avoidance tactics – instead of answering an uncomfortable question, the person takes the conversation somewhere else, often so skillfully that you do not even notice it until the conversation is over.

The trick is that this tactic is often easiest to catch in hindsight. Replay the last few minutes of the conversation in your mind and ask yourself – did the person actually answer what you asked, or did they just talk around it? If you realize that your question never really received an answer, go back and ask it again directly. How they respond to the repeated question will tell you much more than the first answer.

You might also love:

5. Distancing Themselves from Their Own Story

This is one of the more scientifically supported signs that someone is lying. Researcher Matthew Newman and his colleagues found in several studies that when people lie, they consistently use first-person personal pronouns less often, such as “I,” “me,” and “my.” Instead of saying, “I didn’t take the money,” you might hear, “The money wasn’t there.” This small change is not accidental – it reflects an unconscious psychological distancing from one’s own statement, through which the person tries to avoid responsibility.

A large meta-analysis of more than 120 studies on lie detection found the same thing from another perspective: liars generally provide fewer details, sound more uncertain, impersonal, and vague. When someone is not telling a story from their own perspective but somehow “moves” it away from themselves, it is one of those signs that, once you start noticing them, you can no longer ignore.

6. Unconsciously Looking for a Way Out

The anxiety that comes with lying often triggers a physical impulse to withdraw, even when the person is not aware of it. This can show up as looking toward the door, checking the time, crossing their arms, or slightly leaning their body away from you – as if they were already preparing to leave a situation they do not feel comfortable in.

Researchers explain this through the theory of cognitive overload – lying is exhausting, while the body has to simultaneously control what the person is saying and what they are showing. This double task causes control to slip somewhere, most often in small, involuntary movements that the person does not even notice. Investigators regularly observe this behavior during interrogations precisely because it can be one of the more reliable indicators of internal conflict – the person simultaneously wants to remain in the conversation and leave it.

7. Repeating the Same Words or Sentences

“I didn’t take the money. I didn’t see the money. There was no money.” If you have ever heard someone repeat themselves almost word for word, it is not necessarily a coincidence. Repetition works as a mental crutch – the liar sticks to the same wording because it gives them a sense of control and because they are afraid that using different words might cause them to contradict themselves.

Interestingly, repetition is often not intended only for you – the person is also trying to convince themselves. The more often you repeat something, the more true it sounds, even when it is not. So if you notice that the answer to your question barely changes from sentence to sentence, it may be a sign that the person has already prepared that wording in advance.

8. Difficulty Recalling Details Precisely

Real memories are difficult to tear apart, while invented stories tend to fall apart on their own. Psychologists explain this through the theory of “reality monitoring” – real memories contain a huge number of sensory details that you unconsciously pick up while something is happening: a smell, a sound, how bright it was, what someone said in the background. An invented story does not have these details because it never happened – so the person has to construct it again each time, and this is exactly where inconsistencies can appear.

If you ask someone the same question a few days or weeks later and the time, place, or order of events has changed slightly, that is not necessarily a sign of a bad memory. Real memories naturally fade over the years, but they do not “move” – it does not suddenly become a different time or a different place. If, however, you notice that the details of the story actually change from one telling to another, it may mean that the person is essentially inventing them again each time rather than recalling them.

9. Unusual Response Time

Here, the research disagrees somewhat, and that is precisely what makes it interesting. One meta-analysis found that liars do, on average, respond more slowly – logically, because the brain has to suppress the truth while simultaneously constructing a believable alternative, which is simply more work. A newer study conducted in a realistic airport security screening simulation, however, found the opposite: people answered questions they were lying about faster than questions they answered truthfully – as if they wanted to get the uncomfortable moment over with as quickly as possible.

What does this mean for you? The important thing is not the speed of the answer itself, but the deviation from that person’s normal pace. If you actually want to test this, ask them two similar questions – one where you know they will be honest and another where you have doubts. Do not look at whether the answer is fast or slow in itself – look at whether it differs from the pace of the first question. That difference, not the speed itself, is what actually tells you something.