The Science Behind Lying: Key Research About Deception
For Centuries, psychologists, philosophers and students of human nature have been probing how and why humans lie. But it was only in the mid-1900s that the study of deception emerged as a subject of popular scientific inquiry.
From thousands of controlled scientific studies and the field research done during this relatively short period, researchers and criminal investigators have amassed a considerable body of knowledge about deception—and how to detect it using their scientific findings.
Key Takeaways
Here are some of their most remarkable findings so far:
How Often Does Lying Happen in Everyday Life?
Humans are lied to as many as 200 times a day.
Social psychologist Jerald Jellison of the University of Southern California published this figure in his 1977 book, “I’m Sorry, I Didn’t Mean To, and Other Lies We Love To Tell.” The hard-to-believe figure, which of course includes the many innocent “white lies” we hear each day, was given further credence in a 2002 study by Robert Feldman of the University of Massachusetts, who found that on average, people told two to three lies in a ten-minute conversation.
How Good Are We at Detecting Deception Without a Lie Detector?
Humans detect lies with only 54% accuracy.
Our shockingly poor performance at lie detection is just slightly better than if we were to blindly guess. In all of the aggregated studies about how well we detect lies vs. truths, we have never fared better than 57% accuracy. The largest review, encompassing results from 206 academic studies that involved 24,000 individual judgments of lies and truths, found our mean performance to be 54%. Not even weather forecasters are that bad.
You’ve Missed Alot of Lies
Between 75% and 82% of lies go undetected.
Separate studies led by deception researchers Aldert Vrij and Bella DePaulo found that the overwhelming majority of lies went undetected.
Why Do We Lie? Accoring to Social Psychology
Of the lies we tell, 25% are for someone else’s sake.
Lies fall into three broad categories: those we tell for our own benefit, those that benefit someone else, and those that benefit both ourselves and others. A study published in the Journal of Personality and Social Psychology found that at least a quarter of the time, our lies are for another person’s benefit. How thoughtful of us!
At What Age Does Lying Begin?
Children begin deceiving as early as age 6 months.
Dr. Vasudevi Reddy of the University of Portsmouth identified 7 types of deception used by toddlers based on studies of 50 children and interviews with parents. For some, the deception began at 6 months with behavior such as pretend laughter, or crying when nothing was wrong just to get attention.
Do Animals Lie?
Gorillas, fish, birds, even orchids engage in deception.
Humans aren’t the only species capable of lying, of course. What’s surprising is the extent to which other animals and even plants rely on deception to survive. In one comic example, the famous signing gorilla Koko blamed her pet kitten for ripping a sink out of the wall.
The Reality of Avoiding Eye Contact
Avoiding eye contact is the most presumed sign of lying around the world—even though it’s false.
A worldwide study led by researcher Charles Bond found that 72% of people cited avoiding eye contact or averting gaze as a sign of lying, more than any other indicator. Too bad it’s not true. Perhaps this is for part of the reason we’re so bad at detecting lies… we are focused on the wrong clues. People engaged in normal conversation only make direct eye contact 30-60% of the time.
Can the Police Detect Lies?
Law enforcement officials—including FBI agents, customs agents and judges— performed no better than the average person in detecting deception.This shocking stat should put a big smile on a fraudster’s face. A study by Paul Ekman and Maureen O’Sullivan published in American Psychologist found that only members of the U.S. Secret Service consistently fared better than the average person’s 54% accuracy. If you’re an honest person caught up in an investigation, better hope the Secret Service is involved!
Lying in the Courtroom
One in six juries reaches an incorrect verdict.
Now that we know the average person is only 54% accurate at detecting lies, and policeman and judges are statistically no better, this absolutely stunning headline from a 2007 Northwestern University study shouldn’t really come as a surprise. But that doesn’t make it any more acceptable.
How You Can Catch a Liar
Training can improve a person’s lie detection ability by 25-50%. Despite our poor track record at catching lies, all hope is not lost. Several independent studies have found that training in the verbal and nonverbal clues of deception can significantly raise a person’s lie detection capability. Take advantage of the liespotting tips on this site and in the book, Liespotting, to improve your skills.
Frequently Asked Questions
How do I know if someone is lying to me?
Detecting deception in everyday conversations starts with understanding that most people are naturally poor lie detectors, identifying deception with only about 54 percent accuracy. The research summarized in the article shows that relying on common myths such as avoiding eye contact can lead to mistakes, since eye contact varies naturally and is not a reliable indicator of lying.
Instead, effective detection begins with recognizing how frequently deception occurs and why people lie. Studies suggest people may be lied to as many as 200 times a day, often through harmless social lies. Deception falls into different categories, including lies that benefit the speaker, another person, or both. Knowing these motivations helps place behavior in context rather than jumping to conclusions based on a single signal.
Improvement comes through education and training. Scientific research shows that structured learning focused on verbal and nonverbal clues can increase lie detection ability by 25 to 50 percent, demonstrating that skill development rather than instinct leads to better results.
Can police tell when you’re lying?
Police are not significantly better than the average person at detecting lies, but training in verbal and nonverbal cues can improve your lie detection ability by 25 to 50 percent. Research summarized in the article shows that law enforcement officials, including FBI agents, customs agents, and judges, perform at roughly the same level as the general public, identifying deception with about 54 percent accuracy. A study by Paul Ekman and Maureen O’Sullivan published in American Psychologist found that only members of the U.S. Secret Service consistently fared better than the average person.
One reason for this limitation is that many people rely on incorrect assumptions about deception. For example, avoiding eye contact is widely believed to signal lying, yet research shows this is not a reliable indicator since people normally make direct eye contact only part of the time during conversation. Focusing on inaccurate cues may contribute to missed deception, especially since studies suggest that between 75 percent and 82 percent of lies go undetected.
Why do people lie?
People lie for a variety of social and personal reasons, and research shows that deception often serves a functional purpose rather than simply reflecting malicious intent. According to social psychology findings summarized in the article, lies generally fall into three categories: those that benefit the speaker, those intended to help someone else, and those that benefit both parties. Surprisingly, at least 25 percent of lies are told for another person’s sake, highlighting how deception can be connected to social relationships and communication.
Lying is also extremely common in everyday life. Studies suggest people may encounter deception frequently and that individuals often tell multiple lies during ordinary conversations. This prevalence helps explain why humans struggle to detect deception accurately and why many lies slip by unnoticed.
Research further shows that deception begins early in development, with children demonstrating deceptive behaviors at a very young age. Understanding why people lie therefore requires looking at context, motivation, and social dynamics rather than assuming a single cause or intention.