A coalition of thirty-seven of news organizations—including the New York Times, the Associated Press, NPR, USA Today, and Buzzfeed—filed a legal brief over the weekend in support of Freedom of the Press Foundation’s case demanding that the Justice Department release its secret rules for targeting journalists with National Security Letters (NSLs).

NSLs are controversial (and unconstitutional) surveillance tools that allow the FBI to collect private information in national security cases without any involvement whatsoever from judges or courts. We filed a Freedom of Information Act lawsuit in 2015 demanding their secret rules for using NSLs on members of the media, and Reporter’s Committee for Freedom of the Press filed the amicus brief on behalf of the thirty seven news organization on Saturday. (We also filed a separate brief, which you can read below.)

The case stems from 2013, when it was revealed that the Justice Department secretly spied on journalists at the Associated Press and Fox News in separate leak investigations. After a large public backlash when the surveillance was finally made public, the Justice Department announced an update to their “media guidelines,” which supposedly puts strict rules on how and when the US government can spy on journalists’ emails and phone calls to investigate leaks.

While these new media guidelines cover subpoenas, court orders and warrants, the Justice Department curiously exempted National Security Letters from the rules altogether, claiming in the New York Times that NSLs aimed at the press were subject to a separate—but secret—“strict legal regime.”

In response to our lawsuit, the Justice Department released to us some documents in December 2015 that confirmed that these secret rules do, in fact, exist. However the agency refused to release the specific rules or even acknowledge where the actual rules are located—even though we already know they appear in the classified annex of the FBI’s Department Investigations and Operations Guide, which is published in redacted form on the FBI’s website. You can clearly see the section where they are located here: