The case is Knight First Amendment Institute v. Trump, issued on March 23. The Second Circuit initially decided this case in ... The U.S. government ask the full Court of Appeals to rehear the case en banc, but the Circuit declines to do so. This is not an en banc court. The Second Circuit takes the view that en banc rulings harm collegiality and are presumed correctly decided. That does not stop aggrieved parties from trying.
Here is how Judge Parker opens his ruling.
This case arises from the President’s use of the @realDonaldTrump Twitter account (the “Account”) as a primary vehicle for his official communications. He uses this account to make official statements on a wide variety of subjects, many of great national importance. The public, in turn, is able to respond to and engage with the President and other users on Twitter. In Knight First Amendment Inst. at Columbia Univ. v. Trump, we concluded that this dialogue creates a public forum. 928 F.3d 226 (2d Cir. 2019). We also concluded that when the President creates such a public forum, he violates the First Amendment when he excludes persons from the dialogue because they express views with which he disagrees.Judge Parker addresses the dissenter's view that the Twitter account is Trump's private account and not subject to First Amendment standards. He reprints some of Trump's tweets announcing policy on Iran and other foreign matters, demonstrating that the president uses Twitter to communicate federal policy. While the dissenters claim the President does not exercise “some right or privilege created by the State” when he blocks accounts on Twitter, in part because Trump began using the account before he became president, Judge Parker notes that
When the President tweeted about Iran he was speaking in his capacity as the nation’s chief executive and Commander‐in‐Chief. If that is not a “right or privilege created by the State” it is difficult to imagine what might be. By the same token, when he receives responses from the public to the Account, and when he blocks responders whose views he disfavors, he remains the President. The critical question in this case is not the nature of the Account when it was set up a decade ago. The critical question for First Amendment purposes is how the President uses the Account in his capacity as President.