top of page

The End of Detecting Deception

Since biblical times, humans have sought to detect deception if not for personal reasons, certainly for business. Knowing if someone was lying mattered six thousand years ago every bit as much as it matters today. And for thousands of years, all sorts of efforts were invented to either detect deception or to entrap liars. Everything from closely gazing into the eyes for shiftiness, to hot blades drawn across the tongue (believing that the liar would have a dry mouth), to consulting oracles (who usually gave ambiguous answers), to the pulling of the tail of a camel in a darkened tent (the tails were dusted with charcoal, and thus it was expected liars would not touch the tail and their hands would come out clean), to the more modern use of the polygraph exam; mankind has devoted much effort to discovering lies.

Since 1974, I have been a student of the various techniques being taught to detect deception. After forty-four years of reading the scientific literature, following the work of David Givens, Desmond Morris, Mark Frank, David Matsumoto, Judee Burgoon, Aldert Vrij, Bella De Paulo, Paul Ekman, and others, all people I respect for their research and work, I can only come to one conclusion: there is no single behavior indicative of deception. 

Dr. Mark Frank, professor and Department Chair at the University of Buffalo, who is so generous with his knowledge said it best in a conversation with me years ago, “Joe, there is no Pinocchio effect.” And there isn’t and there has never been. There is no single behavior indicative of deception, not one. Even to those who say, "well we look for clusters of behaviors," they would also be wrong. There are no clusters of behaviors indicative of deception. Not really, not if we are honest.

In 2016, I wrote an article for readers of Psychology Today, looking at over two hundred DNA exonerations. People on death row exonerated after definitive DNA tests confirmed they were not the culprits; it was not their saliva, blood, sweat, or semen found at the crime scene. What was startling when I burrowed deep into all these cases, in each and every instance, the law enforcement officers were sure the suspect was lying, but not one officer could detect the truth. Not one officer believed the suspect when they claimed they did not do it. In other words, and I repeat, they could not detect the truth, but they were certain they could detect deception. This wasn’t just embarrassing—lives were at stake—it was shameful. Shameful that anyone should be falsely accused, but also shameful that not one officer in those 261 cases could differentiate the truthful from the deceptive. Why? Because for decades into the present, law enforcement officers have been taught that they can detect deception through nonverbals, when in fact, we humans are no better than a coin toss at detecting deception—a mere fifty/fifty chance. And that is one way you wind up with the innocent on death row.

But it is not just law enforcement, after the popular TV show Lie to Me came out (premiered on the Fox network), all of a sudden there were hundreds of aficionados teaching others how to detect deception; ignoring or twisting what science actually supported and unfortunately further mucking-up the field with simplistic assertions. Too often a veneer of science was wrapped around one or two examples for general public consumption giving the misleading assumption that detecting deception is not just easy, but that it is assured. That is fallacious and wrong.

If detecting deception were just a parlor game, it would not be an issue, but claiming to detect deception and teaching as much has real life consequences. Those men on death row I spoke of earlier, they were going to executed, because of the false beliefs of law enforcement officers that they could detect deception. People have been fired from their jobs because when questioned they showed signs of nervousness or stress. Relationships have been strained or ruined for similar false assumptions. The public and law enforcement has been fed a lot of nonsense about detecting deception and it’s time to stop. I don’t say this lightly. I come at this from my researching and authoring more than a dozen books on human behavior plus my twenty-five years as an FBI Special Agent — thirteen of which I spent in the Bureau’s elite Behavioral Analysis Program.

For many years, post-trial, I would ask jurors in federal cases, what made them think a particular witness was lying? They would reply that they knew the witness was lying because the witness touched their nose, looked away or up to the right, their skin flushed, touched their lips before answering, rubbed their thumbs together, licked their lips, scratched their ears, or shifted their jaw. Incredible, right? Imagine if that were your life on the line?

If you have been following my writings here in Psychology Today for the last nine years, you know that these behaviors described by jurors above are behaviors that both the honest and the dishonest utilize to pacify themselves when there is stress, when they are anxious, or when confronted with something they are not accustomed to—like a trial for instance or being in front of a group or being questioned in public. What the jurors were seeing were all signs of psychological discomfort, but unfortunately, at some point in their lives someone told them, they saw on television, or they read that these pacifying behaviors (for a complete list of pacifying behaviors see The Dictionary of Body Language, Harper Collins 2018) were indicative of deception. Both the public and law enforcement have been seriously misled.

I think it is time to be honest. I think it is time for those who do research and those who have experience conducting forensic interviews and who teach nonverbal communications to be forthright about this topic and speak the truth. And the truth is that we humans are no better than chance at detecting deception. We have known this since Paul Ekman’s best-seller, “Telling Lies: Clues to Deceit in the Marketplace, Politics, and Marriage” came out in 1985.

That we need to stop associating behaviors indicative of psychological discomfort with deception and acknowledge them purely for what they are: signs of stress, anxiety, apprehension, despair, suspicion, tension, concern, nervousness, etc., but not deception. 

After conducting more than thirteen-thousand interviews in my law enforcement career, I can attest that both the innocent and guilty will, at various times, display all those behaviors researchers, law enforcement, and the public associates with deception depending on circumstances. Why? Because humans are sensitive to their environment, to the presence of others, to questioning by authorities, to environmental circumstances, to nuance in voice, body language, ethnicity, educational factors, social intelligence, among many other factors.

Everything that upsets a daily routine, from being called in by a manager about the missing money from the break room, to being confronted on the street by two police officers their weapons on display, is enough to cause most people to display psychological discomfort. And if the questioning is in any way intimidating, or if the person is shamed in public, you can anticipate pacifying behavior and displays of psychological discomfort from the most innocent. Remember: abnormal displays during abnormal circumstances are normal.

In scores of presentations from Europe to Asia, I have demonstrated that I can take the most honest person and within seconds make them do all those behaviors so often falsely associated with deception, just by sitting closer to them, intensifying my look, blinking less while staring at them, changing the tone of voice, asking personal questions, or merely asking simple questions with ardent suspicion. Confronted with any number of techniques too often found in the law enforcement interview literature, I can turn anyone into a self-pacifying, lip licking, ear and neck flushing, high blink rate mess, if I want to. And that is the problem. What we are witnessing is psychological discomfort and that is all and that is all we should say whether it is induced intentionally, by accident, or through circumstances. To claim that we are seeing indicators of deception when we see these behaviors is frankly dishonest and if the definition of ethics is “that which is befitting another human being” then we are also being unethical.

It is time to stop teaching and preaching that we can detect deception through nonverbals and teach what we can use nonverbals for. What is that? That we humans transmit through our body language, what we think, feel, desire, and fear; and that that we communicate this effectively in real time. That when we are stressed, bothered, disappointed, disturbed, anxious, worried, concerned, uncertain, exasperated, or mad, our bodies reveal that information nonverbally by any number of expressions throughout the body, including through the use of pacifiers or what Paul Ekman calls “adaptive behaviors.” In essence we, all of us, can be “issue detectors” as I often say in my lectures, but that is all. That’s all we can say, that something is wrong or not right—that there is an issue—but no more. 

You may be asking, now what? We move forward, and we teach nonverbals but for what it really is: the study of everything that communicates but is not a word. That body language reflects our physiology, our mental state, our thoughts and emotions, which are fluid and reflexive, subject to both internal as well as external factors. But we also need to teach that we who ask questions can also adversely influence and cause stress on those we are questioning if we are not careful. Perhaps here is where schools should focus, how to ask questions without inducing additional stressors that mask honesty.

Where does that leave law enforcement or any other forensic setting? Where we should always have been—asking more and more questions as neutral collectors of facts. We ask questions and when we see a particular behavior as a result of that question, we come back to that topic and we ask more questions, or we try to determine why that question would cause the person to react that way. We use it to identify leads, or things that are troubling to the person being questioned, but not to accuse of deception. 

In September of 1979, a young investigator asked the mother of a fugitive if she had seen her son recently. She answered “no.” When the investigator asked her if it was possible he was sneaking in to her house while she was at work, she covered her neck with her hand as she answered, “I don’t think so.” She was not asked if she was lying or being truthful, it didn’t matter. The fact that the words “son” and “house” made her cover her neck, was enough information to indicate psychological discomfort. The investigator asked other questions and circled back to that question again, the possibility that her son might be in the house and each time, she unwittingly covered her neck. Again, there was never an accusation that she might be lying, but because the investigator saw the same behavior (covering of the neck and in particular the supra sternal notch or neck dimple—something we tend to do when we are very worried or feel vulnerable) he asked if he could do a quick search of the premises. With her signed consent, the investigator found her son, the fugitive, hiding in the closet. That is how we use this information, to alert us to what bothers others so that we can explore why.

I’ve been at this for more than four decades, I’ve learned a lot about the study of nonverbal communications—both the positive and where it fails us. It is time for all of us who teach to pass on the knowledge that yes there are behaviors that get our attention that that are alerting, that we should pay attention to, but those should serve as a guide to what may be hidden or under suspicion, but nothing more. Psychological distress or discomfort in all its manifestations was never and is not indicative of deception.

Recent Posts

See All


Commenting has been turned off.
bottom of page