In March, Twitter received a US Department of Homeland Security summons asking it to help identify the user or users behind one of the many "ALT" or resistance Twitter accounts that proliferated to criticize President Trump after he took office. Twitter says ordering it to identify users would break the law, and it filed a lawsuit against the US government in the Northern District of California today for trying to compel it to do so. The suit, which The Intercept reported on this afternoon, is here. It names as defendants the Department of Homeland Security and its leadership.

The account Homeland Security wanted unmasked is @ALT_uscis or '"ALT Immigration," which identifies itself as "Immigration resistance... Not the views of DHS or USCIS" and tweets criticism of Trump and his administration. Similar accounts popped up in early January after the National Park Service's official Twitter account began sending out a succession of climate science facts, which was interpreted as an implicit criticism of Trump, and was seemingly silenced for doing so. ALTUSNatParkService popped up to take its place and continue the tweets, and so on.

The irony that the Trump administration would want to crack down on anonymous Twitter accounts is that a large portion if not a significant majority of the bots and trolls on the platform support the President. But Twitter, for better or worse, seems interested in defend the internet practice of semi-anonymity for all of its users.

“A time-honored tradition of pseudonymous free speech on matters of public moment runs deep in the political life of America,” Twitter argues in the court filing. “These First Amendment interests are at their zenith when, as here, the speech at issue touches on matters of public political life.”

The ACLU's Esha Bhandari spoke to the LA Times on behalf of the user or users behind the ALT Immigration account, whom she is representing. “Receipt of a summons like this can have a chilling effect on a wide range of people who speak anonymously or pseudo-anonymously on the Internet, so it’s important to fight,” she told the paper. “We’re going to fight for this user’s right to remain anonymous."

In response to the breaking news story, the ALT Immigration account has received a major spike in followers:

“To unmask an anonymous speaker online, the government must have a strong justification,” another ACLU attorney involved in the case, Nathan Freed Wessler, told the New York Times. “But in this case the government has given no reason at all, leading to concerns that it is simply trying to stifle dissent.”

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