We’re not as good at spotting liars as we think we are, according to psychologist Leanne ten Brinke. On Monday’s episode of the Diary of a CEO podcast, ten Brinke, who is the author of Poisonous People: How to Resist Them and Improve Your Life, spoke with host Steven Bartlett about her research into “dark” personality disorders like narcissism, Machiavellianism, and psychopathy.
As ten Brinke noted, psychopathy isn’t a binary; it’s a spectrum of personality traits, which can include superficial charm, impulsivity, lack of remorse, manipulation, and grandiosity. Many of these traits intersect with those of other “dark personalities,” as ten Brinke refers to them, like narcissism, Machiavellianism, and sadism.
An important element of people with these traits is their inclination to lie, either to get out of trouble, get their way, or put somebody else down. But, as ten Brinke said, “people are not very good at detecting … any kind of lies. On average, people perform at about 54 percent accuracy.”
People commonly think they can detect liars by looking at their smiles and their eyes. But those are generally unreliable metrics.
The myth of smiles and eyes
“People put a lot of stock in the body language, particularly into, like, gaze aversion,” ten Brinke said. So if you go around the world and you ask people what’s the number one cue that someone is lying to you, they will say sketchy eye contact. And there’s no research to suggest that that is true.”
Ten Brinke also discussed research around Duchenne vs. non-Duchenne smiles to determine whether someone is being genuine in their facial expressions. A Duchenne smile includes wrinkling around the eyes, also known as crow’s feet, whereas a non-Duchenne smile only shows activation around the corners of the mouth.
Though many think the concept of a smile not meeting the eyes can indicate a lack of sincerity, this type of smile can also occur when someone is smiling to be polite or for social reasons, not necessarily for ill intentions.
However, as ten Brinke told Bartlett, liars are not impossible to detect.
How to actually spot a liar
There are reliable signs that someone is lying—one of them being “visible cognitive effort.”
“They might be using lots of ums and oz and ers. They might be kind of like throwing their brow, trying to figure things out … So none of these are Pinocchio’s nose, but they are reliably associated with deception,” ten Brinke said.
Knowing what questions to ask someone can help determine if they’re lying or telling the truth.
The first tip ten Brinke suggests is not asking closed-answer questions that let people just say yes or no. Alternatively, focusing on getting more details and having people elaborate will often poke holes in fabrications.
“The most consistent effect we have that differentiates people who are telling the truth from people who are lying is the amount of detail that they give,” ten Brinke said.
Bartlett noted in the episode that when people make partial fabrications, they often focus on tangential details and information not key to the actual matter at hand. This is likely because it is easier to seem truthful entirely when they elaborate on the few elements that are accurate to reality. However, when specifically pressed on key details, liars cannot provide much verifiable information.
“If you just ask, ‘How verifiable was that statement?’ that’s a better strategy for detecting lies than trying to use all these other cues that actually don’t work,” she said.
—Jelinda Montes, editorial fellow
This article originally appeared on Fast Company’s sister website, Inc.com.
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