evidence: Lying is ubiquitous, yet politicians are rarely asked why they do it. Maybe journalists think the reason is obvious; many are reluctant to even use the word lie, because it invites confrontation and demands proof. But the answer could help us address the problem. So I spent the past four years asking members of Congress, political operatives, local officials, congressional staffers, White House aides, and campaign consultants this simple question: Why do politicians lie? [...] Politicians have always played to their base, but polarization has encouraged them to do little else. Now that many politicians speak primarily to their supporters, lying has become both less dangerous and more rewarding. "They gain political favor or, ultimately, they gain election," said Mike McCurry, who served as White House press secretary under President Bill Clinton. As former Democratic Senator Bob Kerrey told me, "It’s human nature to want to get a standing ovation." Lies also provide easy ammunition for attacking opponents—no opposition research required. They "take points off the board for other candidates," said Damon Circosta, a Democrat who recently served as the chair of North Carolina’s Board of Elections.