While Twitter is a platform through which millions of users can instantly share and access real-time information about everything from anti-government protests in Hong Kong to who won the Head of Household challenge on Big Brother, the company itself can say very little about the ways in which federal authorities use Twitter for surveillance; it can’t even reveal if there have been no national security requests. In an effort to poke a hole in that steel curtain, Twitter has sued the Justice Dept., U.S. Attorney General Eric Holder, the FBI and its Director James Comey.

“The U.S. government engages in extensive but incomplete speech about the scope of its national security surveillance activities as they pertain to U.S. communications providers, while at the same time prohibiting service providers such as Twitter from providing their own informed perspective as potential recipients of various national security-related requests,” reads the complaint [PDF] filed in a U.S. District Court in San Francisco.

The company says it submitted a draft of its transparency report to the defendants in April, but in September were told that the information Twitter wants to reveal in that report is “classified and cannot be publicly released.”

The DOJ, et al, apparently believe that it does not fit the framework outlined in the Jan. 27 letter from AG Holder to Facebook, Google, LinkedIn, Microsoft, and Yahoo. That letter gave specific details and conditions under which certain transparency data could be made public.

Twitter contends that the government’s position “forces Twitter either to engage in speech that has been preapproved by government officials or else to refrain from speaking altogether,” and that the government has not demonstrated that it has the authority to “establish the preapproved disclosure formats or to impose those speech restrictions on other service providers that were not party to the lawsuit or settlement.”

Twitter says that the framework put in place by the government even prohibits a company from saying that it hasn’t received any national security requests, or that it hasn’t received any of a particular type of national security request.

“These restrictions constitute an unconstitutional prior restraint and content-based restriction on, and government viewpoint discrimination against, Twitter’s right to speak about information of national and global public concern,” reads the complaint.

The company contends that it has a First Amendment right to respond to users’ concerns by “providing more complete information about the limited scope of U.S. government surveillance of Twitter user accounts.”

This information would include what types of legal process have not been received by Twitter, explains the complaint, which alleges that the Jan. 27 Holder letter is “not a lawful means by which Defendants can seek to enforce their unconstitutional speech restrictions.”

Twitter expanded upon its stance in a blog post this afternoon.

“Our ability to speak has been restricted by laws that prohibit and even criminalize a service provider like us from disclosing the exact number of national security letters and Foreign Intelligence Surveillance Act court orders received — even if that number is zero,” writes Twitter VP Ben Lee. “This is an important issue for anyone who believes in a strong First Amendment, and we hope to be able to share our complete Transparency Report.”

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