Civil rights attorneys are threatening to sue U.S. Rep. Peter King, R-New York, who represents parts of Long Island, over his decision to block users from interacting with his political Facebook page, calling it an “affront to the First Amendment” of the U.S. Constitution.

The New York Civil Liberties Union said in a letter to King this week that if he didn't return access to the Facebook page for those users, they would file a lawsuit in federal court on behalf of a handful of those individuals.

“Silencing constituents for criticizing you is, to borrow language from the [U.S.] Supreme Court, 'censorship in its purest form' that 'threatens the continued vitality of free speech,'” the letter said. “In light of this, it is essential that you promptly unban all those whom you have banned for their critical comments.”

King, meanwhile, argued in a response to the letter to Newsday that he was well within his legal rights to ban users from interacting with the Facebook page. He said the account was paid for and operated solely by his campaign, rather that government staff, and could therefore block users from posting negative comments.

“I'm on 100 percent solid legal ground. That Facebook account is political. It is paid for by my campaign committee. It's the same as having people write negative comments on a campaign brochure and sending that out,” King told Newsday. “They can get their own Facebook account and attack me, rather than me paying for it.”

King's press office did not immediately respond to a request for additional comment Thursday.

But Christopher Dunn, legal director at NYCLU, said in an interview with the New York Law Journal that the Facebook page has been used for more than just campaign activities. In fact, Dunn said, King doesn't operate any other pages on Facebook related to his activities as a congressman. That means users who search for him on the social media platform will only find the one account, which does not immediately distinguish itself as a campaign page.

“There's post after post about him talking about his actions as the congressional representative, starting with that the page is labeled 'Congressman Peter King,'” Dunn said. “I don't think anyone looking at this would see anything other than content about Peter King's actions as a congressman.”

A handful of Facebook users who were blocked by the page initially approached the NYCLU about the issue, Dunn said. That's how they came to find out about it, but they more recently decided to take legal action in the event that King does not restore access for the banned users. The litigation would be brought solely under the First Amendment, Dunn said.

“If he had a truly private page, whether it's a personal page or campaign page, the rules are different,” Dunn said. “We've looked at this page extensively and, by all appearances, this is an official congressional page. As long as he continues to maintain it this way, he has to comply with the First Amendment.”

At least 70 individuals have been blocked from viewing or interacting with the page, according to NYCLU. The lawsuit would be brought on behalf of a handful of those individuals, who said they were banned from the page after posting critical comments of King and his political views.

One user, a resident of Suffolk County, was blocked after commenting on a post in which King congratulated former ExxonMobil CEO Rex Tillerson on his confirmation as secretary of state. The user posted a link showing the amount of campaign contributions the company had made to certain federal candidates, including King, and alleged a connection.

“Money talks, anyone wondering why [t]he Congressman is not expressing any concern or doubt need look no further,” the user wrote before they were blocked, according to NYCLU.

Another Suffolk County resident was blocked after criticizing King for deleting certain comments on the page, a practice that King defended in previous election cycles. The user alleged that King deleted comments that were critical of his upcoming votes, while keeping those that praised his actions in Congress.

“It is either that you don't want to explain it to non-press members or you want all the comments on your post to appear positive,” the user wrote, according to NYCLU. “I'm not sure what is worse, but it is incredibly disappointing you won't engage with anyone unless they're complimenting you.”

The potential litigation has echoes of a lawsuit brought last year against President Donald Trump over his practice of blocking users from interacting with his public Twitter profile. Trump, a frequent user of the social media platform, had previously banned a number of users who were critical toward him on Twitter.

That changed last year when U.S. District Senior Judge Naomi Reice Buchwald of the Southern District of New York wrote in a decision that Trump's Twitter feed was considered a public forum, and therefore should be accessible to those individuals. Buchwald wrote that their interactions with the account were protected by the First Amendment.

“That interactive space is susceptible to analysis under the Supreme Court's forum doctrines, and is properly characterized as a designated public forum,” Buchwald wrote. “The viewpoint-based exclusion of the individual plaintiffs from that designated public forum is proscribed by the First Amendment and cannot be justified by the president's personal First Amendment interests.”

The White House decided to unblock those users from Trump's Twitter profile after the decision, though they've appealed it to the Second Circuit. A panel of judges on the appellate court heard arguments in the case in March, but a decision has yet to be handed down.

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