The acknowledgement comes in a closely-watched lawsuit in which seven Twitter users claim President Trump’s account is violating the First Amendment by excluding them from a government platform.

As the legal filing explains, Trump’s decision to block them means they can’t easily follow his account, or to reply to those tweets from their own Twitter accounts.

Meanwhile, what those users see instead of Trump’s usual tweet stream is this image, which is standard on Twitter when a blocked user tries to see an account:

The new legal filing, a so-called stipulation in which both sides agree to a set of facts, also describes the tweets that led Trump to block the accounts. All of them came as replies to tweets sent by Trump, and included negative messages like “To be fair you didn’t win the WH: Russia won it for you.”

The filing also states that White House Social Media Director Dan Scavino has access to Trump’s account @realDonaldTrump, and that he sometimes posts messages to it on the President’s behalf, as well as to other accounts, including @POTUS and @WhiteHouse. It further notes that Hope Hicks and Sarah Huckabee Sanders, who are two of the administration’s most high profile communications staffers, do not have access to the account.

A First Amendment Right to News from Trump?

While acknowledging that Trump blocks those who criticize him, the White House is also fighting the lawsuit, and claiming that the @RealDonaldTrump account is a personal one and not a government publication. If this is the case, the plaintiffs would not be able to invoke a First Amendment right.

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The Knight Institute for the First Amendment, which is helping the Twitter users with the lawsuit, claim the @RealDonaldTrump account is a form of government speech—akin to a federal website—in part because the President uses it to announce major news or policy decisions. In the filing, the Knight Institute cites examples like two tweets from this summer in which Trump announced the nomination of a new FBI director, and admitted he did not possess tapes of former FBI Director James Comey.

The President’s decision to block the users means they, unlike other Americans on Twitter, are unable to see such news directly or to respond directly to comments on the @RealDonaldTrump account. In the eyes of the plaintiffs, this amounts to an illegal form of viewpoint-based discrimination.

This week’s acknowledgement that the President is deliberately blocking such users based on their views appears to strengthen their case—provided they can persuade a court that @RealDonaldTrump is a government account.

The case has produced a divided response among legal scholars. Some like Professor Eugene Volokh of UCLA are skeptical the case will succeed, in part because there are workarounds that could allow blocked Twitter users to still see the President’s tweets.