What is the most derogatory accusation someone in politics can level at another? “Liar”? Nah. Underhandedness is the way business is done here in the D.C. slime.

Whether it’s spin, obfuscation, hyperbole, dissembling or outright falsification, nearly everybody in this game engages in the agony of deceit nearly all of the time. So no, “liar” is not the ultimate insult. Sometimes, it is even flung at someone in admiration — amazement that someone can get away with blatant fabrication. Exhibit A would be Donald Trump, whose base stands by him as he routinely substitutes fantasy for fact. Now Trump is accusing Jim Comey of lying about him. Whether he’s lying about Comey’s lying, it is still not the worst charge he has Trump can conjure up about Comey.

No, in Washington, or wherever politicians gather to share their self-enriching chicanery, the worst slur you can attach to someone is “leaker.” Even though everyone does it, privately whispering for public consumption is regarded as the original sin in this alternative universe of “alternative facts.” Somebody who violates this cabal’s omerta code is the lowest of life forms — a “rat” or a “squealer.” It’s total hypocrisy, of course, but there was President Trump heaping contempt on James Comey for arranging to have leaked to the press his recollections of the president’s apparent attempts to interfere with the FBI’s investigation into Russia’s interference in the last election, allegedly with the active cooperation of the Trump campaign. The Trumpster was trying to pretend that Comey’s admission that he was a “leaker” was a far worse offence than any possible collusion with Vladimir Putin.

But here’s what’s really laughable about such disdain over “leakers”: If anyone in Washington looks past the smoke into the mirror, he or she will see someone who takes a leak all the time, even while sneering at others who do. Jim Comey himself has constantly railed against them. Donald Trump has built a career on them. In New York, his sharing of self-aggrandizement with reporters was legendary. He even created fictional characters to assist him. Today he and his White House posse provide a constant gush of information. It’s a confidence game, actually, with fact and fiction often indistinguishable.

As a reporter, I deal with leaks all the time. It’s the only way we can accurately report on our leaders’ policies, activities and motivations. Otherwise, we would have to rely on official, authorized announcements, which are nothing more than propaganda. It’s the Faustian deal between newsmakers and newsmakees (journalists) to satisfy the American public’s right to know — make that a citizen’s NEED to know — in a democracy that relies on an informed electorate.

Those who cover all the goings-on must handle this delicate relationship with care. We must always factor in the knowledge and integrity of the person providing the leaked information and what he or she stands to gain. We are irresponsible when we don’t confirm that the “source” knows what he or she is talking about. Hence the term “informed” source.

Frankly, I’ve always wanted to do a report citing an “UNinformed source,” but then I’ve also wanted to go on TV and admit that the live shot I’m presenting with such authority is totally meaningless. What I’ve also wanted to do is shun the leakers, not allow them to hide in the shadows. But then we’d be left with nothing but … how shall I say it … FAKE news. As an aside, it’s safe to assume that anything Donald Trump labels as “fake news” is totally accurate. If he likes a story, it’s probably fiction.

Still, all officeholders and those who want to be claim to despise leakers. It’s phony sanctimony. What they really mean is that they condemn the other guy’s leakers as they jostle to lead our government. And what they really, really mean is they don’t like anything that leaks out of their bubble of phoniness that would expose their many flaws.

Bob Franken is a longtime broadcast journalist, including 20 years at CNN.