The National Security Agency can search Americans' email and phone calls without a warrant because of a rule change approved in 2011, according to a top-secret document given by NSA leaker Edward Snowden to the Guardian.
The newspaper's report comes on the heels of another recent disclosure about the NSA's reach into the digital lives of Americans, including a story by the New York Times that the agency's dragnet is much wider than was believed, and has been sifting through international email and text messages of Americans who mention information about foreign targets.
The loophole allowing the NSA to do the warrantless searches for individual U.S. citizens, using their name or other identifying information, is allowed because of amendments made to Section 702 of the Foreign Intelligence Surveillance Act, the Guardian says. FISA lets the NSA undertake digital hunts of foreign targets — who aren't U.S. citizens and who are outside the U.S. — without a warrant.
The document shared by Snowden shows "this is the first evidence that the NSA has permission to search those databases for specific U.S. individuals' communications," the Guardian said.
Sen. Ron Wyden, D-Ore., a member of the Senate Intelligence Committee who has indicated for months that the NSA has access to more information than officials have admitted, told the newspaper that the change to Section 702 allows essentially a "backdoor search" of Americans' data.
"Section 702 was intended to give the government new authorities to collect the communications of individuals believed to be foreigners outside the U.S., but the intelligence community has been unable to tell Congress how many Americans have had their communications swept up in that collection," Wyden told the Guardian.
"Once Americans' communications are collected, a gap in the law that I call the 'back-door searches loophole' allows the government to potentially go through these communications and conduct warrantless searches for the phone calls or emails of law-abiding Americans."
Greg Nojeim, senior counsel and director of the Washington, D.C.-based Center for Democracy and Technology Project on Freedom, Security and Technology, told NBC News that recent government "assurances that Americans needn't worry about NSA surveillance that targets people abroad ring hollow when the 'take' from that surveillance can be searched for the Americans' communications within."
"As it turns out, Americans are targets, too, just one step down the road," he said.
Meanwhile, NSA Director Keith Alexander, speaking Thursday at a cybersecurity conference, said the agency plans to eliminate about 90 percent of its system administrators to reduce the number of employees with access to secret information. Snowden, who was one of those administrators, faces criminal charges by the U.S., but has been granted temporary asylum by Russia.
"No one has willfully or knowingly disobeyed the law or tried to invade your civil liberties or privacies," Alexander said at the conference in New York. "There were no mistakes like that at all."
This story was updated at 3 p.m. ET.