Knight First Amendment Institute v. Trump

Knight First Amendment Institute v. Trump, 928 F.3d 226 (2nd Cir. 2019), was a Second Circuit Court of Appeals case on the use of social media as a public forum. The plaintiffs, Philip N. Cohen, Eugene Gu, Holly Figueroa O'Reilly, Nicholas Pappas, Joseph M. Papp, Rebecca Buckwalter-Poza, and Brandon Neely, were a group of Twitter users blocked by then-U.S. President Donald Trump's personal @realDonaldTrump account. They alleged that Twitter constitutes a public forum, and that a government official blocking access to that forum violates the First Amendment. The lawsuit also named as defendants White House press secretary Sean Spicer and social media director Dan Scavino.

The plaintiffs were represented by the Knight First Amendment Institute at Columbia University, which itself was a plaintiff in the case. Though the Knight Institute's Twitter account had not been blocked by Trump, the lawsuit argued that they and other followers of the @realDonaldTrump Twitter account "are now deprived of their right to read the speech of the dissenters who have been blocked". The complaint also argued that posts to the @realDonaldTrump account are "official statements". The Second Circuit largely agreed, holding that Trump was a state actor for First Amendment purposes because he held out his personal Twitter account as an official account for conducting official business.

However, in 2021, the U.S. Supreme Court vacated the decision because, pursuant to established precedent on the mootness doctrine, the appeals process could not conclude before the swearing in of Joe Biden as President. In addition, the reasoning of Knight was abrogated by later Supreme Court decisions, particularly Lindke v. Freed, which applied a narrower, two-pronged "actual and purported exercise of authority" test.