The House of Representatives on Thursday approved an effort to rein in government surveillance by passing an amendment that attempts to block so-called "backdoor" searches by the NSA.

The late night vote on the amendment, whose main sponsor was Rep. Thomas Massie (R-Ky.), passed 293-123 with overwhelming bipartisan support and little debate.

Massie and amendment co-sponsors Reps. Jim Sensenbrenner (R-Wis.) Zoe Lofgren (D-Calif.) called their proposal "a sure step toward shutting the back door on mass surveillance," and stated that it would "reinstate an important provision that was stripped from the original USA FREEDOM Act to further protect the Constitutional rights of American citizens. Congress has an ongoing obligation to conduct oversight of the intelligence community and its surveillance authorities."

Specifically, the amendment to the 2015 Department of Defense Appropriations Act would "prohibit use of funds by an officer or employee of the United States to query a collection of foreign intelligence information acquired under FISA using a United States person identifier except in specified instances."

In other words, as a group of privacy advocates and tech companies wrote in a letter (pdf) to House members,

the amendment would address the “backdoor search loophole” by prohibiting the use of appropriated funds to enable government agencies to collect and search the communications of U.S. persons without a warrant using section 702 of the Foreign Intelligence Surveillance Act (50 U.S. C. 1881a), a statute primarily designed to pick up communications of individuals abroad. Although section 702 prohibits the government from intentionally targeting the communications of U.S. persons, it does not impose restrictions on querying those communications if they were inadvertently or incidentally collected under section 702. Moreover, as a result of an apparent change in the NSA’s internal practices in 2011, the NSA is now explicitly permitted under certain circumstances to conduct searches using U.S. person names and identifiers without a warrant.

The amendment would block the Defense Appropriations Bill from funding the NSA to conduct this kind of backdoor search.

Mike Masnick writes at Techdirt that the vote marks

the first time that Congress has overwhelmingly voted to defund an NSA program. Last year's Amash Amendment came very, very close to defunding a different program (the Section 215 bulk records collection program), but by passing by an overwhelming margin, this vote is a pretty big sign that the House (on both sides of the aisle) is not happy with how the NSA has been spying on Americans. [...] it's also a big slap in the face to the White House and certain members of the House leadership who conspired to water down the USA Freedom Act a few weeks ago, stripping it of a very similar provision to block backdoor searches.

EFF said the vote marked "a great day in the fight to rein in NSA surveillance abuses." Mark Rumold, staff attorney fir EFF, said in a statement:

The House voted overwhelmingly to cut funding for two of the NSA's invasive surveillance practices: the warrantless searching of Americans' international communications, and the practice of requiring companies to install vulnerabilities in communications products or services. We applaud the House for taking this important first step, and we look forward to other elected officials standing up for our right to privacy.

Fight for the Future, which also supported the amendment, cheered the vote's passage, tweeting on Friday:

We did it!!! Amendments to DoD Appropriations bill passed overwhelmingly. The tides are turning and Congress is scared. #NSA, you're losing!

— Fight for the Future (@fightfortheftr) June 20, 2014

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