There may be no better window into President Trump's mind than his prolific Twitter feed — an unvarnished digital log of what's piquing the leader of the free world in real time.
But when Trump blocks critics from reading and replying to his tweets, it violates protections guaranteed under the 1st Amendment, say free speech attorneys.
In a letter to the White House on Tuesday, the Knight First Amendment Institute at Columbia University called on the president to stop blocking users, arguing that the @realDonaldTrump handle with its nearly 32 million followers amounts to a "designated public forum" that all Americans should have access to — even opponents.
"This is a context in which the Constitution precludes the president from making up his own rules," Jameel Jaffer, the Knight Institute's executive director, said in a statement. "Though the architects of the Constitution surely didn't contemplate presidential Twitter accounts, they understood that the president must not be allowed to banish views from public discourse simply because he finds them objectionable. Having opened this forum to all comers, the president can't exclude people from it merely because he dislikes what they're saying."
The Knight Institute is representing two Twitter users, with potentially more to come, who say they were blocked by Trump's private account for criticizing the president.
One was Holly O'Reilly (@AynRandPaulRyan), who was blocked May 28 after she tweeted a GIF of Pope Francis raising his eyebrows at the sight of Trump. Above it, she wrote: "This is pretty much how the whole world sees you."
The other was Joseph M. Papp (@joepabike), who replied to a Trump weekly video address June 3 by writing "Greetings from Pittsburgh, Sir" and "Why didn't you attend your #PittsburghNotParis rally in DC, Sir?" He was blocked the following day.
Lawyers for the Knight Institute, which threatened to take legal action, said the Twitter blocks were tantamount to a City Council blocking critics from attending a council meeting.
"It would be like telling them to wait in the hallway," said Katie Fallow, a senior litigator for the group.
But calling Twitter a public forum may be a stretch, legally speaking, said Michael Overing, a lawyer and adjunct professor at USC who specializes in 1st Amendment law.
Overing said courts would most likely deem a public forum a physical venue like a park or town hall, not a social media platform. He also argued that Trump has 1st Amendment rights on Twitter that could supersede those of the people he blocks, and that not everyone gets the right to respond to the president's statements — not unlike a news conference, where only some reporters get the opportunity to ask a question.
"Twitter certainly doesn't want to be a public forum," Overing said. "If it were, they couldn't shut down an account in the absence of a true threat.… Think about the L.A. Times having no editorial control over their content because it is a public forum."
Blocked users can still see Trump's tweets when logged out of their accounts or when the tweets are embedded on other Web pages. But Fallow said the blocking still creates an unnecessary burden on some Americans to see what their president has been saying. Blocked users also don't have an opportunity to engage with Trump's tweets, creating an environment where dissent is stifled in the replies.
It's unclear how many people are blocked by Trump. Twitter won't comment on individual accounts. A search on Twitter shows a numerous people claiming to be blocked.
The White House could not be immediately reached for comment.
A Los Angeles Times story in December on the subject showed that ordinary people, including stay-at-home-moms and high school students, were not immune to Trump's blocking.
Despite mounting criticism, Trump and his surrogates have long argued that Twitter is essential to the president, describing it as the only way to circumvent critical media.
"The FAKE MSM is working so hard trying to get me not to use Social Media. They hate that I can get the honest and unfiltered message out," Trump tweeted Tuesday. MSM is short for mainstream media.
The Knight Institute said it did not believe that Trump was blocking users from his official Twitter handle, @POTUS, an account with nearly 19 million users that is typically less combative in tone.
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4:35 p.m.: This article was updated to include comments by 1st Amendment lawyer Michael Overing.