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NBC Insider The Irrational

Myth Or Reality? The Science Behind Reading Body Language, as Practiced by Jesse L. Martin on The Irrational

From hand and eye movement to shifting weight, experts weighed in on the accuracy of body language reading as seen in the new NBC drama The Irrational. 

By Caitlin Schunn
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Understanding human behavior is a complex and arduous task, but a behavioral scientist is up to the challenge in a new NBC fall drama called The Irrational. The character of Alec Mercer, portrayed by Law & Order’s Jesse L. Martin, offers his expertise on behavioral science to law enforcement, corporations, and even governments. Whether it’s negotiating a hostage situation or helping to prove a murder suspect’s innocence, Alec Mercer uses tricks like body language to assess the situation.

How to Watch

Watch The Irrational on NBC and Peacock

But just how accurate is the practice?

Is body language reading real?

“It’s both a myth and a reality,” Dr. John Paul Wright, a professor of criminology at the University of Cincinnati, said of body language reading in an interview with NBC Insider. “Human beings are quite capable liars, and they oftentimes engage in deception, and they use their body. Their body is like camouflage for the words they’re using.”

Dr. Wright pointed out some law enforcement use the practice as part of their day-to-day efforts to find and stop criminals.

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“The focus on subtle body language is more art than science,” Dr. Wright said. “I know some cops that are very, very good at it."

Body language reading can be an incredibly important tool when interviewing suspected criminals.

Alec and Marissa appear in The Irrational.

“These [behavioral] anomalies provide important cues and valuable insight into the personality, motivation, and intention of suspects,” the FBI cited in its publication called Reading People. “These crucial bits of knowledge give investigators information superiority that can guide them through the process and help them complete interviews. Individuals typically do not know that they are revealing these indicators.”

Dr. Wright agreed there are cues to pick up.

“Oftentimes it’s not what they tell you that’s important, it’s what they leave out. It’s lying by omission that’s oftentimes the most important,” Dr. Wright said.

Of course, it's important to note it's not a precise science, and there are other reasons why people may use certain body language.

What body language could indicate a person is lying?

Although it’s not an exact science or absolute indicator of guilt, Dr. Wright said there are some tells that could possibly indicate a person is lying.

Those behaviors include eye movements to the right or left, and an unwillingness to look a person in the face while talking to them, according to Dr. Wright. Another sign could be an over-relaxed body position. On the opposite end of the spectrum, some people tap their hands or feet, or shake their heads while lying.

“The criminal lifestyle is all about manipulations and conning people,” Dr. Wright said. “Some of the body language could be exaggerated hand, eye, and body movements. It’s using the body, if they’re conscious of it, as a method of deception.”

But just because someone is avoiding eye contact doesn’t always mean that person is lying — reinforcing the idea that body language reading is an art, not a science.

Two anonymous people having a conversation using their hands

“A common belief is that a lack of eye contact is an indicator of lying; however, numerous studies have tested this and most do not support it,” the FBI said. “Therefore, this belief is more myth than reality. A recent study showed that liars know this too, and compensate for it by looking the interviewer straight in the eye more than truth tellers.”

What body language could indicate innocence?

Just as body language could mean someone is lying, it could also mean someone is telling the truth. The biggest indicator of innocence often is cooperation.

“They want to prove their innocence. I think that’s a fairly normal response,” Dr. Wright said. “So, on 911 calls where something’s happened, someone is telling them what’s going on, where they’re cooperating with police, where someone is trying. Just imagine yourself — you’ve been accused of something serious, you’d lawyer up and respond immediately.”

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Although telling big, unlikely stories seems like it would be an indicator of lying, that’s not always the case.

“Here’s the other side to that …t he craziest story may be the true one, and that’s what makes detecting some of it so difficult,” Dr. Wright said.

Looking for indicators of innocence can be just as difficult as looking for indicators of lying.

“In real-life, indicators of veracity and lying occur simultaneously, and awareness of both increases an investigator’s ability to identify meaningful content areas of an interview; detect clues to deceit; and provide additional insight into the thoughts, feelings, personality and motivation of the interviewee,” the FBI said.

The bottom line: Body language reading could be a useful tool — but not the defining tool of an investigation. The FBI recommends using witness statements, forensics, and other evidence along with suspect interviews.

“Behavioral anomalies are signs investigators can use to determine truth; however, they should not be interpreted strictly given that research has not identified any behavior or behavior combinations that are unique to lying,” the FBI said. “Using behavioral anomalies in investigative interviewing will not solve every case.”

Watch how Jesse L. Martin’s Alec Mercer uses behavioral science and body language reading to solve crimes when The Irrational premieres Monday, Sept. 25 at 10/9c on NBC and the next day on Peacock.

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