5 KEYS TO KNOW IF SOMEONE IS LYING AND DETECT LIES - GEOGRAFÍA - 2025

Detecting lies is possible if you know how, and especially if you practice observing people. According to psychologist Robert Feldman, who has spent more than four decades studying the phenomenon of lying, people lie on average four times during a conversation with a stranger or acquaintance. Some people even lie twelve times during that period.

In this article I will explain how to know if someone is lying from the observation of body language; facial and physical signs that can give away a liar.

People lie in almost any context, from intimate relationships (marriage or dating) to the most causal. Some lies are small ("you look better, you have lost weight") and others are larger ("I have not been with another woman / man"). Sometimes they hurt the other person and sometimes they don't.

Signs to discover lies

According to the popular and best-known literature, these are the non-verbal signals that are usually made in lies.

Remember that they must be evaluated in context. However, we'll see later what the research says about our ability to detect lies and catch liars.

Non-verbal and paraverbal language

-Microexpressions: these are facial expressions that people show and that are almost imperceptible since they appear in a fraction of a second. Some people can detect them but most cannot. In a person who lies, micro-expression would be an emotion of stress, characterized by raising eyebrows and causing expression lines on the forehead.

-Asent or denial: if the head nods or denies in opposition to what is said, it may be a sign of contradiction.

- Touching the nose and covering the mouth: according to this signal, people would tend to cover their mouths and touch their nose while lying. It could be due to an increase in adrenaline in the capillaries of the nose. On the other hand, putting the hands near the mouth would have the objective of covering the lies.

-Eye movement: it is assumed that you can know, from the movement of the eyes, if a person is remembering or inventing something. When people remember details, their eyes would move up and to the left if they are right-handed. When they invent something, their eyes would move up and to the right. The opposite would work for lefties.

-Poor eye contact: In reality, contrary to popular belief, a liar does not always avoid eye contact. The human being avoids eye contact and looks at objects naturally to focus and remember. In fact, it has been shown that some liars tend to increase the level of eye contact because it has always been considered a sign of sincerity.

-Restlessness: it is when a person looks for something around him something or his body moves restlessly. It is assumed that when telling a lie, anxiety would be produced that would be released with physical movements, compulsively touching a part of the body, etc. It is about observing if the behavior is different from how the person normally behaves.

-Speak slowly: when telling a lie, the person may pause while speaking to find what to say.

-Movement of body parts: arms, hands and legs. In a comfortable situation, people tend to take up space by extending their arms and legs. In a person who lies, her position would remain closed; hands would touch your face, ears, or the back of your neck. Closed arms and legs and lack of movement can be a sign of not wanting to give information.

Emotions and physiology

-Sweat: it seems that people tend to sweat more when they lie. In fact, measuring sweating is one of the ways that the polygraph determines a lie. Like the previous ones, individually it cannot be a reliable indicator. Some people may sweat more because they are more nervous, introverted, or otherwise physically fit.

-False emotions: when a person lies he tries to show an emotion that he does not really feel. You might try to smile when you feel anxious.

-Throat: a person who lies may swallow constantly.

-Breathing: a liar tends to breathe faster. The mouth may appear dry because of stress which causes the heart to beat rapidly and the lungs to demand more air.

-The emotion and what the person says are not simultaneous: for example, someone says "I love it" when receiving a gift and later smiles, instead of smiling at the same time that they say they love it.

-The expression is limited to the mouth: when someone falsifies emotions (happiness, surprise, sadness…) they only move their mouth instead of their entire face: jaw, eyes and forehead.

Message content

-Too many details: when you ask someone something and they respond with too many details, it could mean that they have thought too much about how they are going to get out of the situation and formed a complicated answer as a solution. I would try to give more details to appear more credible.

-Inconsistencies in the story: if the person lies, the story could change each time it appears on a topic of conversation. You could forget something, add something new, or delete something that was mentioned before.

-Avoid lying: instead of making direct statements, they answer a question by "detours". For example, if you ask her "Did you hit your wife?" She might reply, "I love my wife, why would I do that?"

-Use your words to answer a question: to the question «Did you eat at home? The liar might say, "No, I didn't eat at my house."

Interaction and reactions

-A liar feels uncomfortable being face to face with the person who asks him and could turn his body in another direction.

-It may be that a liar unconsciously places things between himself and his interlocutor.

-A person who feels guilty will become defensive. The innocent person will often go on the offensive.

Other signs

-Establish a baseline of how the person normally behaves. If it goes out of it, you will know that something is out of the ordinary.

-If you think someone is lying, unexpectedly change the topic of conversation and observe. It may be that if the person lied, they feel more relaxed. A person who lies wants to change the subject; an innocent person may be confused by a quick change of conversation and may comment on it or want to return to the previous topic.

The reality of lie detection

According to research, it seems that when trying to tell if a person is lying by looking at their non-verbal and paraverbal language, we are often wrong. According to Leanne ten Brinke, a University of California psychologist whose work focuses on detecting deception, "The empirical literature does not support all of these popular arguments."

This lack of coincidence between the popular conception of a liar and reality, supports that really, and despite our confidence in detecting lies, we do not have as much ability to tell when a person lies.

Psychologist Paul Ekman, professor emeritus at the University of San Francisco, has spent more than half a century studying the nonverbal expressions of emotion and deception. Over the years, he has had more than 15,000 subjects who have watched videos of people lying or telling the truth on various topics. He confirmed that the success rate in identifying honesty has been 15% in all of these subjects.

However, Ekman found that one particular feature could be useful. These are micro expressions (discussed in the previous point); almost imperceptible facial movements that last thousandths of a second and that are extremely difficult to control consciously. The problem is that they are too complex to detect and of the 15,000 subjects only 50 people could identify them.

We are good unconsciously and bad consciously

For Brinke, one of the world's experts on deception, something about the current literature on lies does not make sense. Why would we be so bad at something that is so necessary? If cheating signals took so much time and energy to learn, they wouldn't be of much help.

Maybe we are not so bad at detecting lies. It may be that the researchers have been asking the wrong question. It may not matter so much the conscious detection of the lie, but the ability to unconsciously perceive:

In a series of studies in the journal Psychological Science, a University of Berkeley research team had students watch videos of potential criminals asked if they had stolen $ 100.

The suspect answered random questions ("What clothes are you wearing? What's the weather like?") And key questions ("Did you steal the money ?," Are you lying? "). Half of the suspects lied and the other half told the truth. Each participant saw a video of a truth and another of a lie.

The students then completed a simple assessment: Who is telling the truth? As in previous studies, very few participants got it right.

However, the participants performed two unconscious lie detection tasks. In each task, they saw photos of two suspects along with words related to truth or lies.

The goal was for the participants to categorize the words as indicative of truth or lie, as quickly as possible, regardless of the photo of the suspect they saw next to it.

Example: A photo of a suspect is shown to a subject and at that moment a word appears on the screen, such as "sincere." At that moment, the participant must press a button to classify that word in the category of truth or lie.

After this, the researchers observed that in this unconscious way the participants obtained better results. They were quicker to categorize words related to truth or lie when presented with photos of suspects telling the truth or a lie respectively.

According to Brinke; " When you see the face of a liar concept of deception is activated in your mind even if you're aware of it. It is not yet clear what percentage of lies the unconscious mind can detect, but this is definitely the case. '

On the other hand, researcher André Reinhard from the University of Manheim found that his study participants were more accurate in detecting a lie when they were prevented from thinking consciously. It states that unconsciously the brain has time to integrate signals that the conscious mind cannot perceive.

"You can fool everyone for a while, but you can't fool everyone, all the time."