The Justice Department will appeal a federal judge's ruling that President Trump can't legally block people from his @realDonaldTrump Twitter account based on their political views, according to court documents filed late Monday.

Last month, Judge Naomi Buchwald said in a 75-page decision that Trump's effort to silence his critics on Twitter is not permissible under the Constitution because the digital space where he engages with constituents is a public forum.

While all seven Twitter users who sued Trump over the issue are now unblocked, they're disappointed with the government's decision to appeal the "court's thoughtful and well-supported ruling," said Jameel Jaffer, the executive director of the Knight First Amendment Institute, which represented the users. "We look forward to defending the ruling in the Second Circuit,” Jaffer said in a statement Monday, referring to the U.S. Court of Appeals for the Second Circuit in New York.

The Justice Department declined to comment. The White House did not immediately respond to a request for comment.

The administration had previously argued that the First Amendment does not apply to Trump in this case because he was acting as a private individual. Outside experts have argued that Trump's Twitter account and even the parts of it where people engage with the president don't constitute a public forum, which would grant the president the freedom to block individuals.

At a time when public officials are increasingly using social media to speak with constituents, experts say the Twitter case is significant because it could set important rules around how elected officials can shape online debate. It also raises questions about how far social media users’ right to speech may extend.