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The U.S. Court of Appeals for the 2nd Circuit in New York said Trump's Twitter account is an official line of communication with his 74.9 million followers, the Washington Examiner reported. Trump often uses the platform to endorse or rail against policies or political rivals.
"Excluding people from an otherwise public forum such as this by blocking those who express views critical of a public official is, we concluded, unconstitutional,” wrote Judge Barrington Parker, later adding: "Twitter is not just an official channel of communication for the President; it is his most important channel of communication."
A federal appeals court last year ruled that Trump isn't allowed to block people on Twitter over statements he doesn't like. The court said because he uses Twitter to communicate with the public about his administration, it warrants constitutional free speech protections under the First Amendment.
Two Trump-appointed judges on the court disagreed with the panel's ruling, saying elected officials have a right to have private social media interactions.
"The First Amendment’s guarantee of free speech does not include a right to post on other people’s personal social media accounts, even if those other people happen to be public officials," Judge Michael Park said.
The ruling stems from a 2017 lawsuit filed by a free-speech group against Trump. Trump, who uses his @realDonaldTrump account, was sued by the Knight First Amendment Institute at Columbia University, along with several individual users who claim Trump's blocking them on Twitter violates the U.S. Constitution.
"This case should send a clear message to other public officials tempted to block critics from social media accounts used for official purposes," said Katie Fallow, one of the attorneys from the case, according to the Examiner.
Other lawmakers have also been sued for blocking users over the social media platform. Rep. Alexandria Ocasio-Cortez, D-N.Y., faced a lawsuit from former Democratic New York Assemblyman Dov Hikind for blocking critics. Ocasio-Cortez apologized to Hikind for blocking him and they reached a settlement.