In an attempt to assuage public fears that it has not been granting the National Security Agency "unfettered access" to user data, Google has penned an open letter asking the United States government for permission to disclose information about the secret court orders the king of search receives.

David Drummond, Google's chief legal officer, writes that "Google has worked tremendously hard over the past fifteen years to earn [its] users' trust," and that it has "consistently pushed back on overly broad government requests" for user data.

Assertions in the press that our compliance with these requests gives the U.S. government unfettered access to our users' data are simply untrue. However, government nondisclosure obligations regarding the number of FISA national security requests that Google receives, as well as the number of accounts covered by those requests, fuel that speculation.

We therefore ask you to help make it possible for Google to publish in our Transparency Report aggregate numbers of national security requests, including FISA disclosures — in terms of both the number we receive and their scope. Google's numbers would clearly show that our compliance with these requests falls far short of the claims being made. Google has nothing to hide. [Google]

Shortly after Google published the letter, Microsoft and Facebook quickly issued similar statements. The Department of Justice acknowledged that it has received these letters, and is currently "in the process of reviewing their request," reports CNET.

The PR blitz comes on the heels of reports from the Guardian and the Washington Post trumpeting that the NSA has had "direct access" to the servers of Google, Microsoft, Facebook, Yahoo, and several other internet companies as part of its PRISM surveillance program, which gathers emails, videos, and online chats to ostensibly protect the country against terrorist threats. The Post later softened its language to suggest the NSA's access wasn't as unrestricted as initially indicated.

(Related: 6 reasons you should, and shouldn't, freak out about the NSA data-mining)

Over at Wired, Kim Zetter reports that instead of relying on direct access to servers, Google transmits FISA information to the government either by hand or via secure FTP — not some open cookie jar like The Post initially suggested. "When required to comply with these requests, we deliver that information to the U.S. government — generally through secure FTP transfers and in person," Google spokesman Chris Gaither tells Wired. "The U.S. government does not have the ability to pull that data directly from our servers or network."

The FBI and the DoJ have the authority to prohibit companies from talking about user-data requests they receive from the government — a law Google hasn't exactly been vocal about opposing till now.

"You have to wonder, then, why Google has never tried to change this law, when there have been opportunities — these FISA amendments have faced reauthorization every year since their introduction in 2008," argues Sam Biddle at Valleywag:

But despite, according to federal disclosure data, spending over $44 milion on general lobbying to date and enjoying 37 employees on federal advisory committees, Google has not once lobbied regarding FISA when it's faced congressional reauthorization. Why not try to change the law with part of your war chest? [Valleywag]

It is, however, clear why Google is speaking up now. As Jordan Novet says at GigaOm:

... the perception of complicity is something Google and the rest must fight. Whether or not the federal government complies with requests for more transparency almost doesn't matter. The companies need to at least look like they want to shed light on their involvement and the extent of the data mining. And the letters achieve that goal. [GigaOm]