Shep Smith breaks his silence about why he left Fox News

New York(CNN Business) Shep Smith, who left Fox News in October 2019 while in the middle of a three-year contract, has remained largely silent about his departure -- until an interview with CNN's Christiane Amanpour that aired Tuesday.

Smith, now host of the nightly show "The News with Shepard Smith" at 7 pm ET on CNBC, told Amanpour that his presence on Fox became untenable as opinion shows on the network spread falsehoods that hosts knew were lies.

"Opine all you like, but if you're going to opine, begin with the truth and opine from there," Smith said. "When people begin with a false premise and lead people astray, that's injurious to society and it's the antithesis of what we should be doing: Those of us who are so honored and grateful to have a platform of public influence have to use it for the public good."

Smith, who joined Fox News at its inception in 1996, said he was proud of the work he did at the network, hosting a daytime news show that was increasingly at odds with what was being aired on Fox's opinion shows. Smith felt that by sticking with Fox News, he could counteract falsehoods spread by Sean Hannity, Tucker Carlson, Laura Ingraham and other prime-time hosts.

"I thought it was important that I stay there," he said. "If you feel like the Fox viewers were getting mis- or disinformation, I was there to make sure that they got it straight," he said.

Smith thought depriving viewers of news and replacing it with opinions "felt a little selfish," he added.

But in the end, staying felt impossible, CNN Chief Media Correspondent Brian Stelter reported shortly after Smith's departure. The breaking point for Smith came as tensions with the opinion shows were getting to be too much.

For example, in late September 2019, 8 pm ET host Tucker Carlson mocked Smith for standing up for his friend and colleague Judge Andrew Napolitano after the judge was called a "fool" by one of Carlson's guests. The network's lack of a vocal defense for Smith following the incident bothered him and the whole episode factored into his decision to leave, according to a person familiar with the matter.

Executives at the network leaned on him to stay, but they were unsuccessful. Smith announced his departure on air, then exited the building immediately.

"I stuck with it for as long as I could," Smith said. "At some point, I realized I've reached a point of diminishing returns, and I left."

Smith told Amanpour that he continues to be disturbed by what is reported on Fox.

"I don't know how some people sleep at night," Smith said of the Fox News employees who knowingly spread falsehoods. "I know that there are a lot of people who have propagated the lies and who have pushed them forward over and over again who are smart enough and educated enough to know better."