George Santos has been accused of lying constantly. This is what experts say about the psychology of compulsive liars.

• Rep. George Santos has been accused of lying about events from the serious to the insignificant.
• Experts said pathological lying could exist on its own or be a feature of a personality disorder.

Rep. George Santos has been accused of being a fantasist, a fabulist, and an outright liar.

Each day appears to bring new allegations about the New York congressman.

He has gone by multiple names, admitted to lying about his college education and work history, falsely claimed he has Jewish heritage, and made multiple bizarre and disproved claims about his mother either dying in or being present during the 9/11 attacks.

Mired in scandal, Santos has said he will step down from serving on committees in the House of Representatives while he faces multiple investigations.

While everyone tells lies occasionally, some people appear to do so much more than others. So, why and how do people become compulsive liars? This is what the experts say.

What is a compulsive liar?

Christian Hart, a professor of psychology at Texas Woman's University who specializes in pathological lying, told Insider that the terms "habitual liar," "compulsive liar," and "pathological liar" essentially mean the same thing — people who lie a lot.

Hart said that compulsive liars typically engage in excessive lying that causes some problems in the normal functioning of their lives, whether with work, romantic relationships, or with friends and family.

They typically have some kind of internal conflict over the lies, he said, as they want to stop but find themselves compulsively engaging in the behavior over and over again.

While Hart said he can't formally diagnose the lawmaker without knowing details about whether he experiences functional problems or distress, he notes that Santos does appear to engage in pathological lying.

"In the sense that most people use the term 'pathological lying,' I'd say yes, it seems like he's got this long track history preceding his entering into politics where he's cultivated this reputation of being an extremely dishonest person," Hart said.

So why do people lie? Hart explains that people don't lie unless there is some incentive to do so — though this incentive might not always be obvious to an outsider.

Many of Santos' lies appear to serve a clear purpose. He embellished his résumé while on the campaign trail, likely in an attempt to impress voters. He fabricated connections to the 9/11 attacks, possibly in order to burnish his reputation as a true New Yorker or to garner sympathy.

But along with lying about details about important elements of his life and history, Santos has also appeared to tell outlandish lies about seemingly insignificant things.

He has claimed that he was a successful volleyball player at the university he lied about attending, once allegedly told a former roommate that he was a model, and claimed to have acted in the "Hannah Montana" Disney movie.

"When people have historically defined pathological lying, many of them have said these people lie with no apparent reason. But I argue that it does serve a purpose, it's just a purpose that we are unfamiliar with," Hart said.

Santos, Hart said, "lied about being a star athlete on a volleyball team at a kind of a lower-tier college — that wouldn't carry any cache for most people. But just because we can't see the purpose of the lie doesn't mean the purpose doesn't exist for him. Perhaps, he's always had a sense of inferiority about not being an athletic person, and so to be seen that way means a lot to him where it would mean nothing to other people."

A representative for Santos did not reply to Insider's request for comment.

Hart has written a book about the science of pathological lying along with his colleague Drew Curtis, who is a psychology professor at Angelo State University.

Curtis told Insider that, like many psychological tendencies, pathological lying is often due to a combination of factors involving environment and genetics, both nature and nurture, and typically begins in later childhood and adolescence.

Do compulsive liars know they're lying?

Many psychologists say compulsive lying is often a feature of a personality disorder, such as antisocial-personality disorder or narcissistic-personality disorder.

Compulsive lying is not, in itself, classified as a disorder in the DSM, the handbook healthcare professionals use as the guide to classifying mental-health disorders.

Curtis explained that it is important to distinguish people who are just pathological liars, and those that engage in pathological lying as part of a personality disorder — a key difference being that pathological liars do typically exhibit some remorse about lying.

While again Hart said he can't formally diagnose him, he said Santos does appear to exhibit some traits of antisocial-personality disorder — where people manipulate and exploit others for personal benefit, with little guilt or remorse.

"Looking at the types of things that historically Santos has been accused of lying about and given his reaction when he's confronted about those instances of dishonesty, he certainly seems that he could have many of the traits of antisocial-personality disorder," Hart said.

Along with being accused of lying about things to boost his reputation, a military veteran has also accused Santos of pocketing $3,000 from a GoFundMe page for a dying dog, which the FBI is now probing.

Peers and the public have also raised questions about the congressman's personal and campaign finances, which he is facing federal and local investigations over.

Typically, compulsive liars believe they won't be caught and that any negative consequences from their lies are tolerable, according to Hart.

However, Santos' lies are often well-documented, as he puts them in writing on social media or his websites, or verbalizes them in on-camera interviews.

Hart noted that it is "unusual" that Santos does not appear to be concerned about others discovering his lies and, in fact, "appears to just double down in many cases when he's accused of lying."

"That is unusual for him and unusual for many of the cases that we've explored of pathological liars," Hart said. "It looks to me like he's the type of person who doesn't seem to worry too much about the reputation he's cultivating around his honesty or dishonesty."

When people lie constantly and repeatedly, it can be easy to question whether they are even aware that they are lying any more and whether they have simply become detached from reality.

In a recently leaked audio recording from January 30, obtained by Talking Points Memo, Santos admits to his track record of lying and appears to express frustration with himself.

"I've made bad judgment calls, and I'm reaping the consequences of those bad judgment calls," Santos said in the recording.

"I've obviously fucked up and lied to him, like I lied to everyone else," Santos later said, apparently referring to his chief of staff Charley Lovett. "And he still forgave me and gave me a second shot, unlike some other people."

Curtis noted that the fact that Santos has admitted to lying about some aspects of his past suggests a conscious deception.

"I think in the case of Santos, he's come out, at least from my understanding, he's come out and apologized and said, you know, this wasn't necessarily true. So then if someone's claiming that what they said wasn't true, then I think it's easier to say that was a deception, not a delusion," Curtis said.

Professions like politics are more closely linked to lying

Curtis and Hart note in their research that certain professions, like sales and politics, are more closely linked with lying.

Hart explained that these professions do not necessarily attract dishonest people, but might push people toward dishonesty. For example, a salesperson may be dishonest if they must sell an inferior product. Similarly, politicians might not be able to be honest all of the time and so might find themselves exaggerating, concealing, or outright lying about things.

He noted that politicians who are willing to tell lies are actually more likely to get reelected than politicians who are unwilling to be dishonest.

How do you deal with compulsive liars?

Curtis and Hart note that pathological lying can be difficult to treat as it is not a formally recognized diagnosis.

As it currently stands, psychologists typically treat pathological liars with cognitive-behavioral therapy, a common type of talk therapy.

Outside of a professional setting, it can be hard to know how to respond to a compulsive liar. Hart suggested that the best way to respond to pathological liars is to call them out on their lies.

"Most people don't like being called out on their lying and feel extremely uncomfortable, and they want to prevent any further reputational damage," he said.

Curtis suggested ignoring the deception and intentionally giving attention to honest behavior instead.

"One of the real challenges of how to respond to pathological lying is that we give attention to their lies, which then can become reinforcing. So one of the suggestions we have is called 'differential reinforcement of other behavior,' where you ignore the deception. Then you have to intentionally give attention to honest behavior," Curtis said.

"So, even when honesty may be mundane, not very exciting, we need to give that attention to the person who lies a lot."