Ex-Washington Post fact-checker Glenn Kessler offered a warning to his ex-bosses in their efforts to court conservatives, something he suggested could alienate their liberal readership.In his Substack piece about what led him to leave The Post after 27 years, Kessler recalled an April 2024 meeting he had with the paper's new CEO and publisher Will Lewis, who had just assumed the role earlier in the year."It was strange for me to have an hour-long meeting with the publisher of the newspaper," Kessler told Fox News Digital in an interview. "I've never had such a long period of time with the publisher of the newspaper."WASHINGTON POST BOMBARDED WITH CAKE PARTIES FOR DEPARTING STAFFERSBut what irked Kessler at the meeting was the question Lewis asked him: "What should The Post do to appeal more to Fox News viewers?""He kind of, I felt, was crossing a bit of a business-newsroom line where he was asking my advice on how to make the newspaper appeal to different audience," Kessler said. "As I write in the piece, frankly, the audience of The Washington Post is mostly liberal. I mean, this is based on my anecdotal evidence based on if I wrote fact checks that gave Pinocchios to Democrats, I got lots of angry emails. If I gave fact checks that gave Pinocchios to Republicans, I didn't get that many emails. And so it was an indication of where his thinking was.""And as I said, it would be a good idea to broaden the readership base of the Washington Post to bring in more conservatives," he continued. "But the question is, how do you do that without losing your liberal readers?"WASHINGTON POST REELING FROM BUYOUT EXODUS AS BOSSES HOPE TO TURN THE PAGE AT EMBATTLED PAPERKessler went on to cite the "real-life experiment" that put the question to the test, pointing to billionaire owner Jeff Bezos' decision to halt the planned endorsement of then-Vice President Kamala Harris just days before the presidential election, followed by the launch of his new mission in February for the editorial pages to promote "personal liberties and free markets."Both instances, which on their surface appeared to be overt gestures to appeal to non-liberals, sparked rebellion among the paper's liberal readers, leading to the cancellation of hundreds of thousands of subscriptions."So that shows the difficulty," Kessler said. "It's literally like trying to change engines on an airplane mid-flight."LONGTIME WASHINGTON POST FACT CHECKER TAKES BUYOUT, SAYS PAPER HAS YET TO FIND REPLACEMENT BEFORE EXITKessler recalled telling Lewis that The Post had to "remain true" to its journalistic principles and "provide compelling, interesting news reporting.""You can make sure that the news reports themselves don't have any particular edge or bias that might be viewed as kind of a liberal lens versus a conservative lens," Kessler told Fox News Digital. "But like I said, it's a very tricky thing to do when probably 75, 80% of your readers are liberal."The former Post fact-checker went on to criticize Bezos' editorial mission, which the owner said explicitly would not publish pieces that go against the principles of personal liberties and free markets. The directive caused consternation within The Post, so much so that multiple staffers resigned in protest."I don't understand the idea of eliminating liberal voices from the editorial page because a traditional newspaper editorial page has a lot of debate," Kessler said before pointing to conservative columnists that have appeared on The Post's opinion pages, namely Marc Thiessen and the late Charles Krauthammer."And I've always advised college students when they start reading newspapers or setting up their Twitter feeds, I always say, follow people or read people you disagree with because you're going to learn much more from people you disagree with than people you agree with," he continued. "And there's some columnists I never bother to read because they're always saying the same thing, and it's not interesting, and I prefer to be challenged and prefer to have my thinking, you know, shocked into, 'Oh, I'm looking at this wrong.' So the idea that you're going to just have kind of a one-sided debate is a strange way to run a newspaper."A spokesperson for The Washington Post told Fox News Digital, "The Washington Post is committed to producing high-quality journalism and riveting storytelling to reach all audiences. The Post is dedicated to delivering world-class news experiences to serve all of America."Fox News' Annie McCuen contributed to this report.