Justice Department officials have filed a “secret lawsuit” that would force Google to deliver private user data to the government in the absence of a warrant, and without notifying the person being probed by law enforcement.

DOJ filed the lawsuit on April 22, about two weeks before news broke that government lawyers had seized Associated Press phone records. “[The lawsuit] offers a rare glimpse of how determined prosecutors are to defend a process that allows federal agents to gain warrantless access to user records, and how committed the Mountain View, Calif., company is to defending its customers’ privacy rights against what it views as illegal requests,” according to CNET, which first reported on the lawsuit.

The case involves the FBI’s use of national security letters, government requests for data that do not require a warrant and often come with a gag order, a ban on revealing that the information was requested.

“Under the Electronic Communications Privacy Act (ECPA) 18 U.S.C. section 2709, the FBI can seek ‘the name, address, length of service, and local and long distance toll billing records; of a subscriber to a wire or electronic communications service,” Google posted in an online statement on March 5. “The FBI can’t use NSLs to obtain anything else from Google, such as Gmail content, search queries, YouTube videos or user IP addresses.”

CNET notes that “the litigation over NSLs began three weeks” after Google published that statement.

There’s a lot more on this story, which you can read here.