Over the past month, President Trump has been called a “pathological liar” by presidential candidate Bernie Sanders, Congressional Representative John Geramendi, talk show host Jimmy Kimmel, and actor Patricia Arquette. In fact, if you look at the critical media coverage of our current President, it appears to be one of the most commonly tossed out accusations. But, it’s clear from the context in which these words are spoken, that many people who use this term have no idea what it really means. Let’s take a closer look at the psychology of lying.

The Truth About Lying

If you believe the research, we’re all liars. Here’s an example; two decades ago social psychologist Bella DePaulo and her colleagues asked 147 adults to keep a diary for a week of every time they told an untruth. Most diary keepers averaged 1 or 2 lies a day. Most were relatively harmless and were motivated either by an attempt to spare someone’s feelings (no, you don’t look fat in those jeans) or make an excuse for not completing a task (I thought it was your turn to do the dishes). 

A later study by these same researchers was a little more alarming in that it showed that many people have, at some point, told a more “serious” lie, such as putting false information on a job application or misrepresenting their relationship status to a person they were attracted to. Ironically, research also shows that we’re just as hard-wired to trust people as we are to occasionally tell a small fib. If you ask someone what they do for a living and tells you she is a physician, most of us aren’t sitting there’s thinking: “Maybe she’s not really a doctor.” We are especially gullible to accepting lies that please us (flattery), comfort us (the promise of success) or that affirm our worldview (political or religious beliefs). This gives liars a natural advantage.

Social Norms About Lying

Here’s the silver lining in the cloud of deception; while most of us lie, most of us only lie a little bit. This is true even when we have a financial incentive to do so. For instance, in one study, college students were given a test consisting of 20 math problems, asked to complete as many as possible, and told their pay would depend upon their number of correct answers. At the end of the test, they were told to shred their test sheets and verbally report how many they got right. Of course, the test sheets weren’t actually shredded; the researchers wanted to see how the answers the student volunteers actually got right in comparison to how many they said they did. 

On average, the students said they successfully completed 6 math problems when, in reality, they completed 4. This pattern was consistent across cultures and did not matter whether the payment per successfully completed math problem was low or high. Apparently, most of us want to see ourselves as honest and, even with a clear financial incentive to do otherwise, place limits on how much we are willing to lie. 

The Lying Habit

I once worked with a woman who was a pathological liar. Extremely bright, funny, and articulate, she was initially very popular with her clients and coworkers alike. Over time, though, it became painfully obvious to everyone that she concocted elaborate stories about famous people she knew (celebrities, government officials) and the things she had done (often contradicting herself about her past achievements and activities). Sometimes she seemed to lie about things for no apparent reason. 

Her lies eventually caught up with her after her clients complained to her supervisor. Threatened with the loss of her job, she told coworkers she had been diagnosed with potentially terminal cancer and her entire office rallied around her. Unfortunately for her, another work colleague had recovered from a similar illness and, as weeks passed with no obvious signs of illness or treatment, support turned to suspicion. This led to more illogical and elaborate lies and increasing disgust and scorn from her work colleagues. She was eventually terminated after she began to miss work. 

As you can see, pathological lying is quantitatively and qualitatively distinct from “normal’ lying; it is a compulsive need to lie about matters big and small, regardless of the situation. While most lies are goal directed and for a reason i.e., for personal gain, to avoid punishment, or to escape responsibility, the motivation for pathological lying comes from within – to get acceptance or sympathy, tell something interesting, or make themselves appear special in some way. The attention generated by their lies provides them with a temporary escape from a reality that is perceived as painful or boring. Over time, lying becomes more like a personality trait than a measured choice or defensive response. And it persists even when it has negative consequences for the liar.

Mental Illness and Lying

So where does the line between typical and pathological lying start? We still aren’t sure. There is little agreement among mental health professionals about the relationship between mental health and lying; is it a separate problem or part of a larger issue? 

It does seem that people with certain personality disorders and/or personality traits, tend to exhibit certain patterns of lying. Individuals high on narcissism, for instance, are more likely to tell falsehoods to boost their image. Individuals high on Machiavellianism – a personality trait in which a person is so focused on their own interests they will manipulate, deceive, and exploit others to achieve their goals – is likely to use deception as a means to an end. Individuals who score high on psychopathy are more likely to lie in any number of circumstances, whether it’s for fun (to feel superior to others), the thrill of getting caught, or to gain a person’s trust so that s/he can be exploited.    

The bottom line is that we all lie to some extent, there are different kinds of lies, and there are different motives for lying. Given the fact that we human beings are inherently poor lie detectors and that, in the grand scheme of things, the motives for someone’s lying matter less than the impact the lies have, perhaps we’d be better off discarding verbal insults (disguised as psychological diagnoses) and focus instead on ferreting out the truth behind what we’re being told. Or, as Ronald Reagan said, “Trust, but verify.” 

Trust. But verify.