President Donald Trump cannot block Twitter users from following his personal account, the US Court of Appeals for the Second Circuit ruled Tuesday, affirming a lower court’s ruling that Trump has been violating the Constitution by blocking his critics.

“The First Amendment does not permit a public official who utilizes a social media account for all manner of official purposes to exclude persons from an otherwise-open dialogue because they expressed views with which the official disagrees,” a panel of three Second Circuit judges wrote in a unanimous opinion.

The lawsuit was filed in 2017 by the Knight First Amendment Institute at Columbia University on behalf of a number of people Trump blocked. In May 2018, US District Judge Naomi Reice Buchwald ruled that Trump blocking people constitutes “viewpoint discrimination” that “violates the First Amendment.” (Buchwald suggested in her opinion that he try muting people instead.) Her ruling has now been affirmed by an appeals court.

The appeals court ruling cites a number of instances in which the Trump administration has indicated that tweets the president posts on his personal account are official government statements, as well as times Trump has conducted government business on Twitter, including firing administration officials and conducting high-stakes international diplomacy by tweet.

Because of those tweets, and because of how Twitter works (including the ability to retweet and reply to tweets), the judges ruled that Trump’s Twitter is a public forum and blocking users is unconstitutional.

“Once the President has chosen a platform and opened up its interactive space to millions of users and participants, he may not selectively exclude those whose views he disagrees with,” they wrote.

The US Justice Department hasn’t yet publicly commented on the latest ruling or said whether it will appeal the case to the Supreme Court.

Author Molly Jong-Fast is among the Twitter users whom Trump has blocked since taking office, but didn’t join the lawsuit. And unlike the plaintiffs in the case, she remains blocked.

Jong-Fast told Vox that being blocked by Trump means sometimes looking at her Twitter feed and seeing a string of quote-tweets with “tweet unavailable” boxes in the place of where Trump’s tweets would normally appear.

She says she can’t recall what specific tweet prompted Trump’s team, which includes White House social media director Dan Scavino, to block her, but thinks she may have been a target because her verified status resulted in her replies appearing in prominent places in Trump’s mentions.

Her description of what she’s missing echoed the judges’ opinions: “It definitely feels like Trump’s mentions are like the comment section and that’s a fun place to hang out, and I miss that sometimes,” she said. “Sometimes it’s really weirdly smart people saying, ‘That’s not what happened,’ so that’s interesting, and for me, I’m always curious to see what I’m missing. So yeah, it’s kind of a bummer.”

Jong-Fast said that even if the Second Circuit’s is the final word on the matter and Trump ends up being legally obligated to unblock everyone, she still doesn’t expect to be unblocked.

“I promise you I will never be unblocked because the reality is, even if they say Trump has to do it, when has something being illegal ever stopped him?” she said. “It seems like such a dumb thing to care about, but it’s a larger metaphor for his larger lack of interest in the actual law.”

Read the court’s opinion here, or below.

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