Can You Spot A Lie?

Sept. 6, 2010
It's beneficial to know when the person you're questioning has decided to bolt.

A police officer's job involves dealing with the public; we interact with them each day. Sometimes that interaction is on a proactive level; most times, we are reacting to something, a crime that was committed or a gut instinct we have regarding someone we contact on the street. Regardless of the reason, our course of action is predicated upon on our perception of the veracity of questions we ask.

During my thirty-three years on the job, I ran across my share of citizens who tried to run a game on me. Sometimes I fell victim to their conniving lies; other times I was able to see right through their unconvincing rhetoric and called them on it. Being able to spot deception, verbally and visually, is important. It can mean the difference between grabbing the right suspect, or best-case scenario, saving a life.

I recently spoke with a former colleague of mine, retired FBI Special Agent Mark Bouton. We talked about the best ways to spot deception and lies. Mark worked the street most of his career not only in the U.S., but also in Puerto Rico and Mexico. After thousands of interviews and interrogations, he became adept at recognizing certain indices of deception. He felt what he'd learned was so valuable he decided to write a book on the subject, How To Spot Lies Like the FBI.

One of the more important topics Mark writes about involves field stops: questioning possible crime suspects or merely suspicious people. This is rudimentary police work; we do it all the time. How often does a guy bolt without us ever having anticipated it? Probably more often than we would care to admit. So how do we gain the advantage, how do we recognize the signs he displays which warn us that he's about to beat feet? Some are easy to spot: looking around instead of looking at us; heart racing for no apparent reason; or perhaps breaking out in a sweat, even though the weather is cold.

Mark warns there are other signs easily recognized as indicators of flight. If your suspect's jaw muscles tighten, his lips compress or form a sneer, or if his face reddens, brace yourself; he's ready to run. Watch his eyes, if they narrow and his eyebrows draw closer together, making a vertical furrow in his forehead, he's about to rabbit. If you see a brief flash of an angry expression, then the suspect suddenly looks calm, be wary of him, as his micro expression has signaled his true feelings, and the more placid mien is a cover-up.

Just as important as facial expressions are clues to lying and deception - body language is an equally good indicator. Being cognizant of how a suspect subconsciously signals he's about to attack is critically important. Signs to watch for that could signal possible aggressiveness include clenched fists, or chin thrust forward or raised and looking down at you. Other signs include posturing with the chest expanded, a sudden big intake of air, or feet moved to a defensive position. A suspect may also blade his body to you as a defensive and offensive fighting position.

When we're involved in an interview or interrogation in a controlled environment, e.g., in the police facility, interpreting body language can be of valuable assistance. Being able to watch the individual's entire body as he responds to questions, as well as immediately after he answers, can offer clear indicators that a suspect is lying. Some of these gestures include involuntary touching of parts of the body. If during or after he answers your question he places a finger or hand over or beside his mouth, he has just subconsciously negated what he's told you. In addition, a liar may get a sweaty or itchy neck during the interview, and when he rubs the back of his neck to alleviate those discomforts, he's sending a clear message that he's just been untruthful.

Chemicals called catecholamines are released in the body when someone lies, causing the person's facial area to itch. He will unconsciously scratch his chin, or more commonly, the side of his face. Moreover, the nose is also sensitive to the release of chemicals when telling a lie, and there will be a slight, imperceptible swelling of it accompanied by an itchy feeling. When a person touches his nose, scratches it, or rubs his finger vigorously beneath it during the interview, he's signaling a lack of candor. Similarly, if he rubs his eye, it's a potential signal that he's not being truthful.

It's been said that the eyes are a window to the soul. In police work, they can help us determine deception. People normally maintain eye contact during a conversation about sixty percent of the time. Some will avert their eyes every time they lie. The usual blinking rate is about five to six times per minute, or every ten to twelve seconds. When someone blinks more rapidly, or gives several blinks in quick succession, it's a good indicator that they're not telling the truth. Another signal of deceit is when an interviewee closes his eyes for several seconds before, during, or after answering a question. Their eyelids may even flutter during this closure.

Postures that indicate a person doesn't want to answer questions include leaning away from you, stiffness of the body, crossing the arms on the chest, turning sideways to you, wrapping an ankle around a chair leg, or extending a foot forward as they slouch in a chair and turning that foot on its side. Bouncing or swinging of the foot of a crossed leg indicates nervousness and possible lack of candor. If a suspect turns his body with his feet pointing toward an exit, he's sending a subconscious signal that he wants to get away from the current situation.

I asked Mark his opinion about some of the sociopaths we encounter on the street; you know, the ones who lie more often than tell the truth. Might the same indicators be present in these individuals? He told me a person's psychological makeup can be important in both the signals he gives and the answers he provides. People who are sociopaths are less likely to be as stressed while lying as the normal individual. They won't have the increased heart rate, higher blood pressure, rapid respiration rate, and increased rate of perspiration that people ordinarily exhibit when they're under the stress of lying to a police officer. Also, people who have narcissistic or dissociative personality disorders will react differently when lying.

Being able to identify lying and deception is not only important on the job, it can also come in handy when we're off-duty. Think about dealing with sales people, repairmen, neighbors, even our own family members. Psychological tests indicate that about ninety-one percent of people admit to lying on an almost daily basis. College students lie to their parents in about every other conversation. Children will first conjure up a successful lie at about age five. It's part of growing up and establishing a separate and distinct personality. Until then, they'll exhibit many signs associated with lying such as holding their hands behinds their backs, shuffling side-to-side, looking away, hesitating before answering, stammering, using "ers" and "uhs" more than usual, and touching their mouth or nose.

Mark's thirty years investigative experience helped him catalog a variety of body movements, facial expressions, and verbal responses, allowing him to determine quickly which line of questioning to pursue. His book is a valuable resource for any LEO who wants to tweak his BS antenna; it helped me.

However, a word to the wise: don't leave the book laying around the house. Your spouse may read it. Enough said.

Stay safe, Brothers and Sisters!

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