Here Is One Way to Tell If a Politician Is Lying

Richard Nixon During Speech
Photo-Illustration: Photo: David Kennerly/Bettman/Corbis

A dad joke for you: How can you tell if a politician is lying? The answer: His lips are moving. Really, the line between a dad joke and an NPR joke is a fuzzy one, which is no doubt why this little riddle played a central role in a recent Morning Edition report on some new research about the inaccuracies and untruths politicians tell.

Because, as it turns out, that corny punch line is kind of accurate. Researchers from Millikin University and the University of Wisconsin–Madison analyzed hundreds of statements made by politicians, all of which had been given the PolitiFact treatment. Through their analysis, a pattern emerged: The lies and inaccuracies tended to be expressed through longer sentences, both in scripted speeches and off-the-cuff remarks, reports NPR’s social-science correspondent Shankar Vedantam.

This is not to say that a long-winded politician is always fudging the facts, of course. “There’s no one-size-fits-all rule that says if someone uses a long sentence they’re lying,” Vedantam explained. “In many ways, I think it’s better to think about this as being a flag. It’s like what cops do —  if a police officer sees a car drifting across the lanes, it doesn’t automatically mean the driver is drunk. But it’s a flag that the driver might be drunk, and it might be worth pulling the driver over and giving a Breathalyzer test.”

Other research on dishonesty, incidentally, has suggested that skilled liars are also the best at sniffing out others’ lies, so maybe the best person to spot a lying politician is another lying politician.

Here Is One Way to Tell If a Politician Is Lying