Dismayed by the extent of the government's post-Sept. 11 surveillance activities, which many of them had previously voted to authorize, House lawmakers Thursday approved new restrictions on the National Security Agency that amount to the most sweeping curbs on domestic intelligence-gathering in a generation.
Even supporters of the legislation conceded that it may not fully end the dragnet-style government surveillance of Americans that generated public outcry after former NSA contractor Edward Snowden began disclosing the agency's operations a year ago.
Nonetheless, passage of the NSA reform bill capped a remarkable evolution in Congress, which handed the intelligence community broad surveillance authority after the 2001 terrorist attacks and has now begun, haltingly, to rein it in.
The legislation imposes important new limits on the bulk collection of telephone records, one of the most controversial aspects of the government's heightened data-collection efforts, and requires warrants for individual collection of records.
Critics of the bill say last-minute changes requested by the White House had watered down its privacy protections. But the vote by an overwhelming 303 lawmakers from both parties, Congress' first legislative response to the Snowden revelations, still marked a sharp rebuke of the NSA.
Wisconsin Rep. Jim Sensenbrenner, the Republican who shepherded the 2001 USA Patriot Act that was used to broaden NSA surveillance activities, said the restrictions approved Thursday were an attempt to close loopholes and impose limits after government intelligence agencies misused the powers granted by Congress.
"The NSA might still be watching us," the 18-term lawmaker said after the vote. "But now we can watch them."
In the future, he said, "if the NSA goes too far, Congress will be able to stop it and the American public will be able to know what the NSA is doing."
Rep. Robert W. Goodlatte (R-Va.), chairman of the House Judiciary Committee, said the shift in lawmakers' attitudes toward the NSA shouldn't come as a surprise in light of the agency's actions. "They used [the Patriot Act] for purposes different than what I believe Congress intended, and the vote here reflects that," he said.
Supporters of the bill called it the most significant rollback of government surveillance since reforms enacted in 1978 after the Watergate scandal.
Even privacy advocates who withdrew their support for the bill in recent days because they said the White House had weakened some provisions were calling it an important first step.
"The ship is turning," said Gabe Rottman, a policy advisor in the American Civil Liberties Union's Washington legislative office. "What you got was a clear statement today that bulk collection has to end."
As the legislation, called the USA Freedom Act, heads to the Senate, critics — and even the bill's sponsors — are vowing to add language they say is needed to prevent the NSA from continuing bulk collection tactics.
The issue has drawn together an unusual alliance of conservative libertarians and liberals, who Thursday mustered 121 House members to vote against the measure, mostly because they believed it did not go far enough to rein in the spy agency.
Last year, in the immediate aftermath of the Snowden disclosures, the alliance nearly won a vote to cut funds to the NSA's surveillance program.
At its core, the legislation seeks to end the bulk collection of metadata, the term the intelligence agencies use to refer to phone call times, durations and numbers dialed. The NSA has been collecting metadata, but not actual conversations, on a significant percentage of U.S. phone calls. The extent of the NSA's snooping disclosed by Snowden blindsided even privacy advocates who had long warned of the government's reach.
Under the bill, the NSA may seek access to such metadata from telephone companies and others, but only in response to a court order. That provision tracks a proposal from President Obama this year.
The bill requires the government to limit what it is looking for to a "specific selection" search. Those searches must be approved by courts established under the 1978 Foreign Intelligence Surveillance Act, except in emergency situations, when searches would be allowed for up to seven days.
Lawmakers heralded new transparency provisions that remove some of the secrecy from FISA court proceedings. The government must disclose, within one day to Congress and 45 days to the public, any deviation from the specific selection practice that might permit bulk collections of data. Private companies can also now disclose their dealings with the government, a right that was of keen interest to companies in the technology industry.
"Had this disclosure provision been in the Patriot Act, we would not be here at this time and Mr. Snowden would not have become a worldwide figure," Sensenbrenner said.
In the aftermath of the Sept. 11, 2001 attacks, Congress passed the USA Patriot Act to give the Bush administration surveillance authority to investigate potential terrorists.
But in recent years, attempts to reauthorize the legislation began to run into resistance as lawmakers grew more sensitive to privacy concerns.
Liberals pushed back during the Bush administration and eventually joined with tea party Republicans to oppose some of the powers the government had received. One of the early votes taken by House Speaker John A. Boehner's tea party-fueled Republican majority in 2011 was a surprise revolt over the Patriot Act renewal.
A breaking point was reached last summer when, after the Snowden disclosures, Sensenbrenner threw himself into the reform effort and gave the movement a boost of congressional clout.
Despite the strong support on Thursday, lawmakers were mindful that either another terrorist threat — or another whistle-blower disclosure of spying — could place them in the uncomfortable position of having to explain their votes on such sensitive matters.
"It's always been the balance," said Rep. Nancy Pelosi, the Democratic minority leader, who voted for the measure, calling it a compromise. "How do we protect the American people while respecting their rights and their privacy?"
Criticism of the White House-backed alterations to the bill focused on seemingly small changes in language that might be used to once again justify bulk collection of data. One main argument rested on the definition of a "specific selection" that could justify a search.
In a letter to colleagues urging them to vote against the bill, Reps. Zoe Lofgren (D-San Jose) and Thomas Massie (R-Ky.) warned that "once again Congress risks promoting mass surveillance rather than stopping it."
A senior Obama administration official, granted anonymity to discuss private negotiations, said the intent was not to water down the language but to ensure it would not to impede ordinary investigations, which might require collection of a broad set of data — for example, information on all airline flight information to and from a particular location.
"To be clear, the bill does not include any loopholes for bulk collection, including the NSA bulk telephony metadata program," said Caitlin Hayden, spokeswoman for the National Security Council.