AMNA NAWAZ: Welcome to the "NewsHour."

Three high-profile departures in less than 24 hours marked a shift in the U.S. media landscape.

GEOFF BENNETT: FOX News abruptly announced prime-time host Tucker Carlson is leaving the network effective immediately.

That is just days after the FOX Corporation settled a legal battle over accusations that FOX hosts, including Carlson, aired false election claims.

Also today, CNN host Don Lemon tweeted he had been fired after 17 years at the network, adding -- quote -- "It is clear that there are some larger issues at play."

Lemon had been criticized for controversial comments he made about women and aging on air.

And NBC Universal CEO Jeff Shell was let go Sunday after admitting to an inappropriate relationship with a woman at the company.

We start with a closer look at what's behind FOX's decision to let its highest rated prime-time host go so suddenly.

TUCKER CARLSON, Former FOX News Anchor: Good evening, and welcome to "Tucker Carlson Tonight."

GEOFF BENNETT: For more than six years, Tucker Carlson has been a force in the prime-time cable news landscape, a champion for the Trump era GOP, a bullhorn for conspiracy theories, and FOX News' most popular personality.

TUCKER CARLSON: This is the boldest election interference ever attempted in this country's history.

But in an unexpected announcement today, FOX abruptly severed ties with Carlson, the network saying in a statement only that they agreed to part ways, adding: "We thank him for his service to the network."

JUSTIN NELSON, Attorney For Dominion Voting Systems: Lies have consequences.

GEOFF BENNETT: The announcement comes less than a week after FOX settled an historic defamation lawsuit, agreeing to pay more than $787 million to Dominion Voting Systems for the network's role in promoting lies about election fraud in 2020.

TUCKER CARLSON: You have heard a lot over the past few days about the security of our electronic voting machines.

And this is a real issue.

GEOFF BENNETT: Carlson was a key figure in that case, pushing those false claims and conspiracy theories on FOX's airwaves, despite admitting in private that he didn't believe what Trump and his team alleged, Carlson even calling Mr. Trump a demonic force in a text message late on January 6 2021, according to a court filing.

Still, he staunchly defended the former president and his supporters after the January 6 attack on the U.S. Capitol.

Carlson has repeatedly and falsely argued that the insurrection was actually a false flag plot and that the defendants charged for breaching the Capitol are in fact victims.

TUCKER CARLSON: The DOJ has been allowed to prosecute and jail hundreds of nonviolent political protesters whose crime was having the wrong opinions.

GEOFF BENNETT: Earlier this year, with help from House Speaker Kevin McCarthy, he aired selectively edited security camera footage to promote his case.

TUCKER CARLSON: They're not destroying the Capitol.

They obviously revere the Capitol.

GEOFF BENNETT: Over the years, Carlson's outrage-driven monologues have drawn scrutiny for amplifying and promoting antisemitic, racist, homophobic, and xenophobic narratives, in 2018, losing advertisers after this anti-immigrant tirade.

TUCKER CARLSON: We have a moral obligation to admit the world's poor, they tell us, even if it makes our own country poorer and dirtier and more divided.

GEOFF BENNETT: Carlson has also promoted the so-called Great Replacement Theory, a racist conspiracy theory about a covert effort to replace white populations in majority-white countries.

TUCKER CARLSON: They say it constantly.

The Great Replacement?

Yes, it's not a conspiracy theory.

It's their electoral strategy.

And we know that because they say it all the time.

GEOFF BENNETT: Today, his unexpected departure drew celebration from the left, as the news broke during the daytime talk show "The View."

WHOOPI GOLDBERG, Co-Host, "The View": They thank him for his service to the network and... (CROSSTALK) WHOOPI GOLDBERG: ... contributor.

Wave.

GEOFF BENNETT: FOX says it will rely on a rotation of interim hosts until it names a permanent replacement.

Carlson's departure from FOX News raises many questions about the right-wing network's future.

We're joined now by Brian Stelter, a special correspondent for "Vanity Fair" and the author of "Hoax: Donald Trump, FOX News, and the Dangerous Distortion of Truth."

He's writing a new book about FOX set to be released later this year.

Brian, thanks so much for being with us.

And, Tucker Carlson, as you will know, he gave no indication at the end of his show on Friday that he'd be leaving, and the network was running promos for his show today.

Have you, through your reporting, been able to determine the exact cause of this departure?

BRIAN STELTER, "Vanity Fair": Well, he did have no idea this was coming.

He thought he'd be back at work today.

So did his top producer.

His top producer was also terminated today.

My sense is, is that it is related to the Dominion lawsuit in the following way.

For all the messages that were emerging publicly, like Tucker Carlson calling Trump a demonic force and a destroyer, there's so much more that Dominion and FOX was able to read from Carlson's phone privately that was never seen in public.

It was redacted.

And there's actually hundreds and hundreds of pages of redactions that's part of the public record with the court.

So, whatever Carlson was saying privately, whenever he was texting that's been redacted by FOX, that's probably what led to his ouster.

Now, there's also a pending lawsuit from a former FOX producer who's accused Tucker Carlson of having a misogynistic, sexist workplace.

Put all that together, and there was ample reason to remove him from his show.

GEOFF BENNETT: Well, that former producer, Abby Grossberg, we have a statement from her attorney.

It reads this way.

Part of it reads this way: "Tucker Carlson's departure from FOX News is in part an admission of the systemic lying, bullying and conspiracy-mongering claimed by our client."

Tell us more about this suit, because, as I understand it, it's in its early stages.

And she alleges that the harassment when she worked for that show was so bad that she contemplated suicide.

BRIAN STELTER: That's right.

And she has signaled that she is ready to fight this in court for a long time.

She has filed a discrimination lawsuit, and this could take months or years.

So, I think maybe we should view what's happening the following way.

FOX was willing to settle the Dominion lawsuit.

They maybe want to tie up, clean up some of the other litigation that's pending.

They have got the Smartmatic lawsuit coming, shareholder suits pending, all of this that maybe they just want to try to unburden themselves from.

And they're willing to even let their biggest star go.

There's always been a belief inside FOX that the network is the star, not any single host.

And this moment is the biggest test of that ever, even bigger than Bill O'Reilly, because, right now -- well, no, not right now.

Until today, Tucker Carlson was basically controlling the Republican Party.

Whatever he wanted, he got.

Kevin McCarthy gave him the surveillance tapes from January 6.

When he would survey all the 2024 nominees, all the prospective nominees, they all responded to his survey, but not anymore.

He's disappeared.

GEOFF BENNETT: Well, Tucker Carlson has really evolved over his two decades in television.

He right now or he was a symbol of the most inflammatory right-wing rhetoric, but he didn't start that way.

He started really a sort of a William F. Buckley Jr. conservative.

Track his transition for us and what that suggests about the transformation of the Republican Party.

BRIAN STELTER: Well, I was interviewed with him I'm on MSNBC almost 20 years ago.

He was on MSNBC as a host.

It's impossible to imagine today.

And that's because of the radicalization of not all, but some of the Republican Party.

And Carlson has been a big part of that by promoting conspiracy theories and an alternative reality, where there's always an evildoer, an enemy around the corner, oftentimes an immigrant or a Democrat out to get you.

That's the story he was telling every single night.

And millions of people seemed to believe him because they came back for more.

He was unlike almost everything else on even FOX.

He was kind of an island to himself.

So maybe Rupert Murdoch is trying to clean up his house today.

Or maybe he's just trying to get some lawsuits to go away.

GEOFF BENNETT: Brian, what happens to the Republican Party in this election year with Tucker Carlson abandoning the networks and you could argue the Republican Party's biggest microphone right now?

BRIAN STELTER: Well, this is a supply-and-demand story.

So one of the biggest supplies has been cut off today.

Tucker Carlson is gone.

FOX will figure out how to replace him.

Maybe they will choose a less conspiratorial, less paranoid host.

But the show will go on.

FOX has an addicted audience, a very loyal audience that, frankly, many other media companies would love to have.

But they do that through hyperpartisan programming that actually misleads and distorts the public's perception.

Most people don't want it.

Most people see through it.

But folks like Donald Trump really believe it, and they fall for it.

And that's what we saw play out in the Dominion lawsuit.

Right now, I think what we see is this fracture in the Republican Party.

What direction is it going to head in?

And FOX has an incredible amount of influence over that.

So what I'm curious about now is, what's Rupert Murdoch going to do?

What's his son Lachlan going to do?

Do they want to go the Tucker Carlson route with somebody else?

Or do they want to bring FOX back to a more reality-based, news-based perspective?

Maybe they can take Tucker Carlson's huge salary and hire 100 journalists.

GEOFF BENNETT: We will see.

Brian Stelter, thanks so much for sharing your insights and your reporting with us.

We appreciate it.

BRIAN STELTER: Thanks.