Two weeks ago, the Suffolk County (read: Boston) district attorney sent Twitter a request for "subscriber information" and the "IP address logs for account creation" of a user going by the name of Guido Fawkes. Fawkes is associated with hacker group Anonymous, and has posted names, addresses, phone numbers, and other personal information on police officers in what appears to be a retaliation to crackdowns on Occupy protests. The request was part of a subpoena that demanded information on another username and (oddly) some hashtags — and it also requested confidentiality.
The whole affair became very public when Guido Fawkes posted the subpoena after Twitter sent it to him. It's not the first time Twitter's stood up to law enforcement's requests to keep quiet on subpoenas for user information: back in January, Twitter's attorneys fought the US government to release a request for information on Julian Assange and others associated with WikiLeaks. In a statement, Twitter's said its policy is "to notify our users about law enforcement and governmental requests for their information, unless we are prevented by law from doing so." In the case of the Guido Fawkes subpoena, there was merely a request — not a court order — to keep the subpoena secret, so Twitter sent it along to the user, giving him a chance to make a motion to block it.
While Guido Fawkes didn't move to block the subpoena, the American Civil Liberties Union did. An ACLU attorney made a motion to invalidate the subpoena on First Amendment grounds, but just today a Suffolk County Superior Court judge decided against the ACLU. It's not yet known if Twitter has released the information requested in the subpoena, and it's possible that the ACLU will appeal today's decision. We'll keep you updated as this story unfolds.