A number of GOP lawmakers sent a letter to CNN President Jeff Zucker accusing the network of violating the First Amendment by refusing to air a campaign ad for President Trump's reelection.

CNN refused to run the president's ad earlier this month, which highlighted former Vice President Joe Biden's role in getting Viktor Shokin fired, who was the top Ukrainian prosecutor. Biden's son, Hunter Biden, worked at a company that Shokin had been investigating for corruption, though neither of them was implicated in wrongdoing.

The Oct. 18 letter was led by South Carolina Rep. Jeff Duncan, and was also signed by North Carolina Rep. Mark Meadows, Texas Rep. Louie Gohmert, South Carolina Rep. Ralph Norman, Arizona Rep. Paul Gosar, Texas Rep. Randy Weber, Idaho Rep. Russ Fulcher, Alabama Rep. Bradley Byrne, and Florida Rep. Greg Steube.

“As a press organization utilizing the freedom of the press guaranteed to you in the First Amendment, it is particularly disheartening to see you suppressing the free speech of federal political candidates, potentially in violation of federal law and Supreme Court precedent,” the letter reads, according to Conservative Review.

“As your news organization seems to have lost all sense of objectivity, spinning itself into oblivion to support left-leaning candidates and participating in distortions against conservative candidates, you have still operated within the boundaries of the First Amendment. CNN has the right to spout your political commentators’ opinions while millions of Americans change the channel to something else,” the letter continues.

It also cites the Supreme Court case Buckley v. Valeo, which dealt with free speech for political campaigns. The lawmakers accuse the network of violating the court's decision by airing ads for other candidates, but not the president's.

CNN did not immediately respond to a request for comment.

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