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The US Court of Appeals for the Second Circuit upheld the district court's decision that President Donald Trump's practice of blocking critics on Twitter is a violation of the First Amendment. The Trump administration's request for a rehearing was denied on Monday.

After seven people were blocked on Twitter by the @realDonaldTrump for criticizing his presidency and policies in comment threads, The Knight First Amendment Institute at Columbia University filed a suit in 2017. Last July, a panel of three judges upheld the US District Court for the Southern District of New York's earlier ruling, which said the president's Twitter account constitutes a public forum under the First Amendment. The ruling means the president can't block users on the basis of viewpoint.

"We're pleased that the full appeals court will leave the panel's original ruling in place," Jameel Jaffer, the Knight Institute's Executive Director said in a release Monday. "The ruling is an important affirmation of core First Amendment principles as applied to new communications technology."

The White House didn't immediately respond to a request for comment.