The Best Way to Identify Scammers or Lies
Thomas Ormerod's security team faced a seemingly impossible task.
At European airports, they had to ask passengers about their personal history and travel plans. Ormerod planted several people at security checkpoints who had fictional past histories and future plans, and his team had to figure out who was lying.
In reality, only one in a thousand people they interviewed was lying. Identifying the liars was like finding a needle in a haystack. So what did they do?
One option is to focus on body language or eye movement, right? Actually, this is a bad idea.
Continual research shows that even trained police officers try to detect lies from body language and facial expressions, and success is often accidental. According to one study, out of 20,000 people, only 50 were able to make correct judgments with over 80% accuracy. In most cases, you might as well flip a coin.
Ormerod's team tried different methods and successfully identified fake passengers in most cases.
Their secret? Ignoring a large number of previously accepted deceptive clues and using other very simple techniques from scratch.
Recent research on deception has been disappointing. Most previous work focused on interpreting liars' intentions through body language or facial expressions—blushing cheeks, nervous laughter, and sly glances.
The most famous example is Bill Clinton, who touched his nose when denying an affair with Monica Lewinsky, which was seen as a clear sign of lying at the time.
According to Timothy Levine at the University of Alabama at Birmingham, lying behavior can cause strong emotions—nervousness, guilt, and even excitement about the challenge—that are difficult to control.
Even if we think we have a "poker face," we can still make small movements called "microexpressions" that may betray us.
However, the more psychologists observe, the harder it seems to find reliable clues. The problem is the diversity of human behavior. You may find that someone you know well twitches when telling the truth, but the behavior of other people may be very different; there is no universal body language dictionary.
O'Morod, who works at the University of Sussex, says, "There is no sign that always accompanies deception." "I will nervously giggle, others will become more serious, some will stare at each other, and some will avoid eye contact."
Levine agrees with this view: "The evidence is very clear - there are no reliable clues to distinguish lies from the truth."
Although you may have heard that the human subconscious can notice these clues, this seems to be contradicted by the facts.
Despite these irresistible results, our security still often depends on these mythical clues.
Take the checks that some passengers may have to undergo before a long-haul flight as an example - O'Morod was asked to come up with a solution in the run-up to the 2012 Olympics. He said that in general, security officers would use a "yes/no" questionnaire to understand the passengers' intentions. They have also received specialized training to observe "suspicious signs" that may expose deceptive behavior (such as nervous body language).
"That doesn't provide an opportunity to listen, reflect on credibility, and observe changes in behavior - these are all basic aspects of detecting deception," he said.
He said that existing regulations are also prone to bias - for example, officials are more likely to find suspicious signs in certain ethnic groups. "Current methods actually hinder the detection of deceptive behavior," he added.
It is clear that a new method is needed. But given that only catastrophic results have been obtained in the laboratory, what should the new method be?
O'Morod's answer is very simple: no longer just focus on subtle expressions and behavioral details, but instead focus more on what people are saying, skillfully explore the right "pressure points," and break the disguise of liars.
Principles for distinguishing truth from lies
Omrod and his colleague, Coral Dando from the University of Wolverhampton, have compiled a set of conversational principles that can improve the chances of detecting a liar:
Ask open-ended questions. This forces the liar to expand on their story until they become trapped in the web of deception they have woven for themselves.
Create elements of surprise. Investigators can try to increase the liar's "cognitive load" - for example, by asking them questions that may be confusing or unexpected, or by having them recount events in reverse order - which makes it harder for them to maintain their disguise.
Pay attention to small details that can be verified. If a passenger says they went to Oxford University, ask them to tell you about their commute.
Observe changes in confidence level. Watch how potential liars behave when challenged - they may become more verbose when they feel in control, but their comfort zone is limited; if they feel they are losing control, they may shut down.
The goal is to have a casual conversation, not an intense interrogation. However, under this mild pressure, liars may expose themselves by narrating self-contradictions, obvious evasions, or instability.
"It's important to know that there's no quick fix; we've put together the best methods," Omrod said.
Omrod admits that his strategies are simply common sense. "A friend of mine said I was applying for a patent for the art of conversation," he said. But the results speak for themselves.
The team had some people pretend to be passengers, carrying real tickets and travel documents. They had a week to prepare their stories and were then asked to queue with other real passengers at airports across Europe.
Agents trained in Omrod and Dando's questioning techniques found the likelihood of spotting fake passengers was more than 20 times greater for those using suspicious signs and the probability of finding fraudsters was 70%.
"That's really impressive," said Levitt. He was not involved in the study, but he believes that field testing at airports is especially important. "It's the most realistic study," he said.
The art of persuasion
Levitt's own experience is also compelling.
Like Omrod, he believes that clever questioning designed to expose holes in a liar's story is far better than trying to find obvious signs in body language. He recently conducted a Q&A game in which pairs of undergraduate students could win $5 in cash for each correct answer.
The students did not know their partner was an actor. When the game show host temporarily left the room, the actor suggested that the students cheat by quickly looking up the answers in the game. A few students accepted the proposal.
Then the students all underwent questioning by real federal agents to see if they were cheating. The agents used tactical questions to probe their stories - without paying attention to body language or other clues - and were able to identify cheaters with over 90% accuracy.
In 33 interviews, one expert even achieved 100% accuracy - an astonishing result that surpassed the accuracy of body language analysis. Importantly, a follow-up study found that even novices could achieve nearly 80% accuracy by asking the right open-ended questions.
In fact, investigators are often able to "convince" liars to openly admit to their wrongdoing. Levin said their secret is a simple technique known to masters of the art of persuasion: they begin the conversation by asking students if they are being honest. Getting them to admit to telling the truth makes them more forthcoming later on.
"People want to believe they're honest, which makes them more willing to cooperate," Levin said. "Even dishonest people find it hard to pretend to cooperate, so in most cases you can see who's pretending."
Clearly, some professional detectives may already be using these techniques - but given the myths surrounding body language, it's worth emphasizing how powerful the ability to persuade can be compared to suspicious body language.
Despite their success, Omorogbe and Levin still hope that others will try to replicate and build upon their findings to ensure they are effective in different situations. "We should be wary of one-size-fits-all solutions," Levin said.
Although these techniques are primarily designed to help law enforcement, they can also help you identify scammers in everyday life.
"I've been doing this with my kids all along," Omorogbe said. The main thing to remember is to keep an open mind and not jump to conclusions - just because someone looks nervous or can't remember key details doesn't necessarily mean they're guilty. Instead, you should look for more common anomalies.
There is no foolproof way to detect lies, but with a little wit, wisdom, and persuasion, you can expect the truth to eventually come to light.