Charles Dharapak/AP file photo

Obama Administration Secretly Expanded Scope of NSA Spying to Catch Hackers

The revelation comes days after a law was passed that would curtail some NSA spying programs—but not warrantless wiretapping.

According to classified documents obtained by former security contractor Edward Snowden, the National Security Agency in 2012 expanded the scope of its surveillance to include Americans' cross-border Internet traffic, in an attempt to catch computer hackers operating in foreign countries.

But the documents, which were shared with the The New York Times and ProPublica, show that the NSA went after hackers even if it was unable to show that their attacks were coming from abroad. And "a lot" of data, from communications to personal information, was scooped up in the process, according to one document.

The power to expand the scope of NSA spying came from two secret Justice Department memos that allowed the intelligence agency to begin intercepting traffic passing through the Internet in the U.S. without a warrant.

The revelation comes days after President Obama signed into law the USA Freedom Act, a long-debated bill that curtails some of the NSA's powers authorized by the Patriot Act. The bill did not address warrantless searches.

The Justice Department memos piggybacked on a decision from a secret surveillance court that allowed the NSA to use the program to spy on foreign governments. But the agency complained that often it's hard to pin an intrusion on a foreign power because of the ease with which hackers can mask their location or cover their tracks. The NSA was given approval in 2012 to use the program to catch generally "malicious cyberactivity."

Intelligence officials defended the program as legitimate. "It should come as no surprise that the U.S. government gathers intelligence on foreign powers that attempt to penetrate U.S. networks and steal the private information of U.S. citizens and companies," Brian Hale, spokesperson for the Office of the Director of National Intelligence, told the Times.

At the time that the NSA was granted authority to conduct wiretaps of Internet traffic, Congress was deep in a fight over legislation that would facilitate information-sharing between the private sector and the government so that the government could investigate cyber threats from hackers.

No such legislation was passed then, in part because of concerns that it would impinge on individuals' rights to privacy on the Web. But Congress has put forward similar bills this year in a push for cyber information-sharing legislation.

These new revelations about the NSA's wiretapping could put a damper on those hopes, giving voice to privacy advocates who have maintained concerns that such legislation is a thinly-veiled bid for more surveillance powers.

Although this information came from the trove of documents Snowden obtained during his time as a NSA contractor, Snowden maintains he no longer has the documents. Those documents are likely now held by journalists Glenn Greenwald and Laura Poitras, who worked with Snowden to report on the documents. Poitras is credited as a contributor on the new report.