(AP Photo/Matt Sayles, File)

When Dan Ariely first heard the Brian Williams news — that the popular anchor had apologized for misstatements about a personal experience during the Iraq War — his first thought was about the irony. Ariely, a behavioral economist and Duke professor, had just wrapped up making a documentary on the topic of dishonesty. In part of the film, he features the story of Marilee Jones, the dean of admissions at MIT who admitted to misrepresenting her academic degrees. That section included footage of none other than Brian Williams reporting on Jones' story.

"We finished the movie two days before this broke, and we couldn't decide if we should add something to the movie, or just enjoy the irony," Ariely said in an interview.

Of course, Ariely has given much more thought to why people lie than to that cutting-room decision. His 2013 book The Honest Truth About Dishonesty explored why everyone does it, what subjects people fib about the most and how we lie even to ourselves. He's also thought plenty about what may have led Williams to make the claims he did — and how he should respond now.

We asked Ariely for his take on those points, and he highlighted something he's found in his research on dishonesty: People often cheat and lie to help other people. "We call this altruistic cheating," Ariely said. "In all kinds of cases, people actually take tremendous risk for themselves for the benefit of some other goal."

While we don't know exactly what motivated Williams, the anchor did say in his on-air apology last week that the most recent time he made the claim — in tribute to a retired soldier who provided ground security on the day in question — was "a bungled attempt by me to thank one special veteran and, by extension, our brave military men and women, veterans everywhere, those who have served while I did not."

Could the effort to highlight the work of service members have played a role in why Williams inflated his claims? Ariely thinks it could have. "Look, the guy doesn't need to grandiose himself. His career is going incredibly well. I think the way he was trying to do it was to basically use himself to make this story more interesting, more powerful."

Still, Ariely speculated there's likely more to it than just that. Much research has examined why we have false memories, and he said some of it shows that once there are images to connect with a story, as they would be in a television broadcast, "we start confusing where the story is from," a phenomenon called "source monitoring."

Ariely also cited the increasingly fuzzy line between entertainment and journalism, especially for an anchor who's become known as much for slow jamming the news with late night host Jimmy Fallon as he has for reporting it. "We have to remember that in a world in which he does both news and entertainment, it's incredibly tough for him to keep the boundary," Ariely said.

But if an eagerness to help draw attention to veterans did in fact play a role in Williams' false claims, wouldn't that be a good line of defense? Should Williams explain that his exaggeration sprang from a desire to help? Would the public sympathize with that rationale?

Ariely doesn't think so, even if it were true. He said people tend to think of lies as intentional, or pre-planned. "People don't understand how dishonesty works," he said. "They think it's a little bit like eyewitness testimony, that there's an objective reality. What people don't understand is the fuzzy nature of our reasoning power."

As a result, Ariely said, the public is unlikely to accept an explanation that goes against the way they inherently think about lying. "People are not going to intuit [an effort to help] as the real reason, even though most people do it," he said. "What I do think would help is just asking for forgiveness. We've all had mistakes. It would certainly color him to some degree, but the right approach is just to admit the mistake and move on."

The challenge, of course, is that research also shows people are far more willing to forgive themselves than they are to forgive others. "We see the mitigating circumstances of our own behavior, but for other people, we have much more attribution of personality to what they do," Ariely said. In other words, we can rationalize our own lies as exceptions to who we really are, but are more likely to see another person's false claims as indicative of their true character. For Williams, it remains to be seen whether his previous longtime public image as trustworthy will be enough to override that tendency of ours.

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