Richard Nixon: "I'm not a crook" Bill Clinton: "I did not have sexual relations..." Marion Barry: "It's all made up" John Edwards: "The story is false" Anthony Weiner: "I had no idea what happened..." Eric Massa: "It is not true. Period Rod Blagojevich: "I have done nothing wrong" William Jefferson: "The $90,000 was the FBI's money" Edwin Edwards: "I did not do anything wrong..." Kwame Kilpatrick: "Hell yeah! I want some more At the heart of the "birther" controversy is an argument about political lies Psychologists say politicians stretching the truth is "part of the social fabric" Richard Nixon, Bill Clinton and John Edwards have all been caught up in political deception Washington (CNN) -- Wolf Blitzer and Donald Trump's heated showdown this week over claims of a conspiracy to conceal President Barack Obama's true birthplace was, at its core, an argument about lying. Trump and other "birthers" believe the president, mainstream media outlets, the courts and the state of Hawaii are all lying, conspiring in a cover-up that began with Obama's birth announcement in a Honolulu newspaper in 1961. Those who maintain the president was born in Hawaii -- and has produced an authentic birth certificate to prove it -- believe Trump and the other side are willfully ignoring the facts in front of them and spreading lies for political gain. Despite a frustrated GOP, anti-Obama 'birthers' still persist "It's very complicated, the way we process information," said Ron Riggio, an organizational psychology professor at Claremont McKenna College speaking broadly about the nature of lying. It's the politics of audacity. The more outrageous and audacious the lie is, the more people say 'that's got to be true because why would someone make something like that up?' The rise and fall of John Edwards While many politicians are truthful, honest public servants, too many politicians and their surrogates often lie, and voters often let them get away with it, Riggio contends. In the world of politics, lies are that relative no one really likes but everyone reluctantly invites to Thanksgiving dinner. From Richard Nixon -- "I'm not a crook" -- to Bill Clinton -- "I did not have sexual relations with that woman, Miss Lewinsky" -- to Marion Barry -- "It's all made up... I don't know what happened" -- to John Edwards -- "The story is false... It's completely untrue, ridiculous" -- American politicians have had a history of political deception, or at least stretching the truth. Edwards not guilty on one count; mistrial on other charges In 2007, Edwards, who at the time was a leading candidate for president, lied about his mistress and baby when the National Enquirer caught him at the Beverly Hilton Hotel visiting the child. The jury in his conspiracy and illegal campaign contributions trial Thursday found Edwards not guilty on one of six counts. The judge declared a mistrial on the other five counts. And last year, disgraced congressman Anthony Weiner looked CNN's Wolf Blitzer in the eye and lied when confronted with evidence of illicit Twitter photos. He later admitted the deception and resigned from office. Birther satire: Prove Mitt's not a unicorn "From a leadership perspective, so often the lies politicians are involved in are part of leaving an impression about information," Riggio said. So much of it is the little white lies that are part of the social fabric. But when it crosses the line that the public truly believes is important, then it becomes a big problem. Rep. Mike Coffman, R-Colorado, found himself straddling the line between deception, confusion and evasion after reports leaked that he questioned the president's citizenship at a recent fundraiser. I don't know whether Barack Obama was born in the United States of America. I don't know that," Coffman reportedly said. But I do know this, that in his heart, he's not an American. He's just not an American. Why does Mitt Romney continue to put up with Trump? The ensuing media storm over Coffman's comments forced the congressman to backpedal and issue a statement that he does believe Obama is an American citizen but that the president doesn't share the lawmaker's belief in "American exceptionalism." But Coffman's gaffe seems to fall more along the lines of what some behavioral experts call a dodge or an evade. Most dodgers, they're not lying. They just create a false impression," said Michael Norton, an associate business professor at the Harvard Business School who studies how and why people lie. Occasionally politicians get caught in a lie, but it's quite rare. If they are doing their jobs they don't lie, they just evade. Follow us on Twitter @CNNPolitics Join us on Facebook/CNNPolitics The Pulitzer Prize-winning PolitiFact website has made its mark by grading the shades of accuracy in politicians' statements on the "Truth-O-Meter." "I think voters are well aware that politicians stretch the truth -- sometimes to the breaking point," said Bill Adair, editor of PolitiFact and Washington bureau chief of the Tampa Bay Times. And I think voters are also savvy enough to realize there are shades of gray that turn a seemingly accurate statement into a half truth. However, unlike the days when webs of political deception were tougher to untangle, savvy voters now have more tools on hand. "What's different today is that there is so much information available to help people make sense of the political discourse and discern the difference between an exaggeration and a pants-on-fire lie," Adair said. When Gilberto Hinojosa, who was seeking the Texas Democratic Party chairmanship, declared "a large majority of the Republican Party believes that (Obama) is a Muslim and was born in a foreign country, was not born in the United States," at the Central Texas Democratic Forum last month, the would-be chairman rated a "false" on the Truth-O-Meter. Similarly, most claims about the president's birthplace as Kenya and the falsity of his Hawaiian birth certificate rate a flaming "Pants on Fire" on the Truth-O-Meter. Not that any of those ratings will convince Trump, those who agree with him or those who believe the president was born in America. And it doesn't matter how much or how hard either side defends their position, Norton said. "We're much more likely to notice evasive behavior with politicians we already disagree with," Norton said. But we forget people in our party are doing the same thing.