As psychologists and professors of psychology, we’ve always been interested in how liars mislead others.

So while researching for our book, “Big Liars: What Psychological Science Tells Us About Lying and How You Can Avoid Being Duped,” we gave more than 200 participants who identified as habitual liars the following prompt: “When people lie, they often use strategies to conceal their deception and make themselves appear truthful to others. Describe the strategies that you use when you are lying to others.”

Here are the most common ways liars said they lie:

1. They make eye contact

The group said that they try to maintain or increase the amount of eye contact they make with the person to whom they are lying.

One person wrote, “I look them dead in the eyes.” Others described similar tactics to hold eye contact or said they avoided looking away when lying.

2. They control their facial expressions

Participants reported that they attempted to manipulate their facial expressions to present a believable countenance.

They wrote about trying not to let the look of fear or surprise appear on their face. “I just tried to keep a straight face,” one said.

3. They act calm and confident

People wrote that they tried to maintain a normal demeanor. One study participant stated that they “act as if nothing was wrong or different.”

4. They don’t fidget

People claimed that they intentionally controlled or reduced fidgeting with their hands or feet and otherwise attempted to maintain normal body movements, such as crossing their arms, to minimize urges to fidget.

5. They act emotional

When some people lied, they tried to appear more emotional than they actually felt, such as by feigning upset or crying. They seemed to think that emotionality would convince others of their truthfulness.

6. They manage their tone and pitch

People reported efforts to alter and manage the tone of their voice or their vocal pitch, for example, by trying to have a confident sounding tone of voice, using a serious tone, and trying not to let the pitch of their voice rise.

7. They control the details

People suggested that they worked to manage the amount or the nature of the details and evidence that they shared, withholding key information or sometimes adding details in an attempt to sound convincing.

Simple ways to spot a liar

We’re humans, not walking polygraph machines. But we can use techniques to identify when people are being dishonest with us more readily.

One strategy is to get the potential liar to talk. The more a person talks, the more information they
provide. Each bit of information they offer is something that can potentially be checked out or verified against the evidence.

Another way is to have them repeat themselves. If a person at work claims to have contributed to a major project, for example, wait a week and have them retell their version of events. Liars often change the details between two tellings.

If you notice the inconsistencies, you can reveal the dishonesty.

Christian L. Hart, PhD, is a professor of psychology at Texas Woman’s University. He holds a master’s degree and PhD in experimental psychology and has been a professor for almost 20 years. He is the author of “Big Liars: What Psychological Science Tells Us About Lying and How You Can Avoid Being Duped.” Follow him on Twitter @chrishartpsych.

Drew A. Curtis, PhD, is a licensed psychologist, director of the PsyD and MS counseling psychology programs at Angelo State University, and co-author of “Big Liars.” He also serves as executive officer for the Southwestern Psychological Association and president for Psychological Association of Greater West Texas.

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