First Kathy Griffin and now Reza Aslan. In the past 10 days, CNN has severed ties with two TV personalities for making controversial statements about President Donald Trump — drawing a line on the kind of speech the network will tolerate from its contributors, even when they are off-camera.

On Friday afternoon, CNN announced it had dropped Aslan’s show Believer after the religious studies scholar called Trump “a piece of shit” on Twitter over the weekend. “He’s an embarrassment to humankind,” Aslan also said in the now-deleted tweet.

Last Wednesday, CNN fired comedian Kathy Griffin from its annual New Year’s Eve show after she released a provocative photo of herself holding a bloody model of Trump’s severed head. Griffin promptly apologized after posting the photo, saying that her attempt at comedy “went too far,” but CNN nonetheless let her go the next day.

Aslan also apologized for his choice of words. On June 4, he said on Twitter: “I should not have used a profanity to describe the President when responding to his shocking reaction to the #LondonAttacks.” But on Friday, in response to the news that CNN had canceled his show, he appeared to stand by the underlying sentiment of his tweets.

“I recognize that CNN needs to protect its brand as an unbiased news outlet,” he said in a statement. “Similarly, I need to honor my voice. I am not a journalist. I am a social commentator and scholar. And so I agree with CNN that it is best that we part ways.”

Though CNN has not fully explained why it let Griffin and Aslan go, the sticking point appears to be their vulgarity, not their partisan views.

Both Aslan and Griffin have been longtime critics of the president, and at CNN they did not serve as journalists. Griffin was the comic foil to Anderson Cooper on the network’s New Year’s Eve program, known for her shock comedy and lewd jokes. Aslan was the host of Believer, a travel documentary featuring the world’s different religions.

Neither had much involvement in CNN’s news operation — which itself employs partisan pundits to debate issues on-camera. During the election, for instance, CNN hired Corey Lewandowski after he was fired from his job as Trump’s campaign manager to help viewers understand Trump’s perspective. (Lewandowski later resigned.) The network also employs Jeffrey Lord for the same reason: to add frisson and friction to what might otherwise be a bland newscast.

It’s not unusual for news organizations to set standards for what their employees or freelancers can say in public, though CNN is different from other cable news channels in that it also produces infotainment programs, like Anthony Bourdain’s travel documentary Parts Unknown. In letting go of Aslan and Griffin, CNN seemed to making a statement about the propriety it expects from all of its contributors, whether or not they are part of the newsroom.

Earlier this week, alt-right news website Breitbart fired one of its own writers for making an anti-Muslim tweet following the London Bridge terror attack. “There would be no deadly terror attacks in the U.K. if Muslims didn't live there,” reporter Katie McHugh said on Twitter. McHugh refused to apologize for her statement, pinning the offending tweet to the top of her Twitter page.

“Breitbart News fired me for telling the truth about Islam and Muslim immigration,” she later told her followers.

McHugh’s firing seemed to signal changes at Breitbart, which in the past has tolerated racist tweets from its reporters. Breitbart senior editor Milo Yiannopoulos, an internet personality who has a history of making abusive, racist remarks, resigned only after a video surfaced in February showing him defending pedophilia.

Since the election, there have been concerns that the president is coarsening the way Americans talk to each other. Trump himself has been criticized for bragging about grabbing women “by the pussy” and for mocking a disabled New York Times reporter. Breitbart’s newfound disapproval of racism may reflect a desire to elevate the level of the nation’s public discourse. It may be a similar — if more exacting — impulse that caused CNN to cancel someone’s show for calling Trump “a piece of shit” on Twitter.