Donald Trump lies. Prolifically. That is not news. But a researcher who spent 20 years researching lies, liars, and why people lie, says Trump isn't just any liar—he's an especially mean one too. Social scientist Bella DePaulo studied Trump's first 298 days in office and the 1,628 lies he told and found that he was lying on average about six times per day (and 9 times per day in more recent months), far exceeding the average lie rate of roughly 1.5 per day. And in Trump's case, the only lies we know about are the ones he's told publicly.

But where the Don really set himself apart was in the maliciousness of his lies. Sometimes people lie to protect themselves from embarrassment or even to protect someone else (like telling your mom you don't mind taking her shopping), but Trump is just plain vicious a startling amount of the time.

The most stunning way Trump’s lies differed from our participants’, though, was in their cruelty. An astonishing 50 percent of Trump’s lies were hurtful or disparaging. For example, he proclaimed that John Brennan, James Clapper and James Comey, all career intelligence or law enforcement officials, were “political hacks.” He said that “the Sloppy Michael Moore Show on Broadway was a TOTAL BOMB and was forced to close.” Talking about green card applicants, he insisted that other “countries, they don’t put their finest in the lottery system. They put people probably in many cases that they don’t want.” And he claimed that “Ralph Northam, who is running for Governor of Virginia, is fighting for the violent MS-13 killer gangs & sanctuary cities.” The Trump lies that could not be coded into just one category were typically told both to belittle others and enhance himself. For example: “Senator Bob Corker ‘begged’ me to endorse him for reelection in Tennessee. I said ‘NO’ and he dropped out (said he could not win without my endorsement).”

The effect of all Trump's lying has naturally resulted in Americans largely just not believing him.