This is an interesting argument. I'm persuaded that, say, the Department of Agriculture can't apply viewpoint-based discrimination on whom they choose to block from their Twitter feed.
It's much less clear to me that this restriction should apply to every government official using Twitter in the same manner as a private citizen might. What's the limiting principle? The First Amendment applies just as much at your local school board meeting as it does at a White House press conference; does that mean each of those elected officials must treat their social media accounts as public forums if they ever choose to use them to chat about official business as @realdonaldtrump does?
> I'm persuaded that, say, the Department of Agriculture can't apply viewpoint-based discrimination
I agree. But how far does that go? Lets say there's a small town somewhere that hosts a monthly community BBQ/potluck during the summer. They post photos to the town facebook page, and PETA shows up and starts spamming the comments with "meat is murder" and the like. Can the town block PETA?
This is an issue already dealt with at length in existing case law, and is largely unrelated to the case at hand because @realdonaldtrump is not a place for announcing community events or road closures, and the censorship applied there is not viewpoint-neutral.
Relevant quote from the article: The president has admitted in the lawsuit that he blocked them because he objected to the viewpoints they expressed in replying to his tweets or in their own tweets.
The reason EFF describes that as an "admission", is because it makes the question you raise irrelevant.
Hypothetical: Suppose A is a citizen of the town and one of the PETA supporters, and its thus blocked. Suppose further that they post a bridge out notice, which A cannot receive due to the block.
As for "spamming", there are, our should be, other remedies for such harassment.
It depends on what other limits they place on the use of the town facebook page.
If they consistently apply the rule that only content related to the monthly potluck is allowed, then they would be allowed to block PETA (this is similar to the example the article gives of a public library that hosts a discussion board exclusively for book recommendations). They wouldn't be able to block someone who complained that the food would at the last potluck was bad, because that would be blocking them based on viewpoint rather than based on topic.
The brief/article seems to argue that @realdonaldtrump represents a public forum only because he uses it as such, and they’ve explicitly stated that his posts represent official views of POTUS. To me, that implies that public officials can still have private accounts provided that they don’t use them for official communications.
It's much less clear to me that this restriction should apply to every government official using Twitter in the same manner as a private citizen might. What's the limiting principle? The First Amendment applies just as much at your local school board meeting as it does at a White House press conference; does that mean each of those elected officials must treat their social media accounts as public forums if they ever choose to use them to chat about official business as @realdonaldtrump does?