Minutes before the midnight deadline Thursday, President Obama approved a four-year extension of the government's Patriot Act powers to search records and conduct roving wiretaps in pursuit of terrorists.
"I think it is an important tool for us to continue dealing with an ongoing terrorist threat," the president said from the G-8 Summit in France.
The White House said Obama had signed the bill from Europe using an autopen machine that holds a pen and signs his actual signature. It is only used with proper authorization of the president. The action comes a month after intelligence and military forces hunted down Usama bin Laden.
Following the 72-23 Senate vote, the House voted to approve the bill 250-153 with hours to go before the three terror-fighting tools were set to expire.
The measure extends the legal life of roving wiretaps, court-ordered searches of business records and surveillance of non-American "lone wolf" suspects without confirmed ties to terrorist groups.
The roving wiretaps and access to business records are small parts of the USA Patriot Act that was enacted after the Sept. 11 attacks in 2001. But unlike most of the act, which is permanent law, those provisions must be periodically renewed because of concerns that they could be used to violate privacy rights. The same applies to the "lone wolf" provision, which was part of a 2004 intelligence act.
Earlier, the Senate struggled to find a way to stage a final vote in the face of continued resistance from a single senator, Republican freshman Rand Paul of Kentucky.
Paul argued that in the rush to meet the terrorist threat in 2001 Congress enacted a Patriot Act that tramples on individual liberties. He had some backing from liberal Democrats and civil liberties groups who have long contended the Patriot Act gives the government authority to spy on innocent citizens.
Sen. Mark Udall, D-Colo., said the provision on collecting business records can expose law-abiding citizens to government scrutiny. "If we cannot limit investigations to terrorism or other nefarious activities, where do they end?" he asked.
"The Patriot Act has been used improperly again and again by law enforcement to invade Americans' privacy and violate their constitutional rights," said Laura W. Murphy, director of the ACLU Washington legislative office.
But intelligence officials have denied improper use of surveillance tools, and this week both FBI Director Robert Mueller and Director of National Intelligence James Clapper sent letters to congressional leaders warning of serious national security consequences if the provisions were allowed to lapse.
The Obama administration says that without the three authorities the FBI might not be able to obtain information on terrorist plotting inside the U.S. and that a terrorist who communicates using different cell phones and email accounts could escape timely surveillance.
"When the clock strikes midnight tomorrow, we would be giving terrorists the opportunity to plot attacks against our country, undetected," Senate Majority Leader Harry Reid said on the Senate floor Wednesday. In unusually personal criticism of a fellow senator, he warned that Paul, by blocking swift passage of the bill, "is threatening to take away the best tools we have for stopping them."
The nation itself is divided over the Patriot Act, as reflected in a Pew Research Center poll last February, before the killing of bin Laden, that found that 34 percent felt the law "goes too far and poses a threat to civil liberties. Some 42 percent considered it "a necessary tool that helps the government find terrorists." That was a slight turnaround from 2004 when 39 percent thought it went too far and 33 percent said it was necessary.
Paul, after complaining that Reid's remarks were "personally insulting," asked whether the nation "should have some rules that say before they come into your house, before they go into your banking records, that a judge should be asked for permission, that there should be judicial review? Do we want a lawless land?"
In practice, law enforcement has used the three provisions sparingly. According to a senior Justice Department national security official testifying to Congress last March, the government has sought roving wiretap authority in about 20 cases a year between 2001 and 2010 and has sought warrants for business records less than 40 times a year, on average. The government has yet to use the lone wolf authority.
But the ACLU also points out that court approvals for business record access jumped from 21 in 2009 to 96 last year, and the organization contends the Patriot Act has blurred the line between investigations of actual terrorists and those not suspected of doing anything wrong.
Two Democratic critics of the Patriot Act, Sen. Ron Wyden of Oregon and Udall of Colorado, on Thursday extracted a promise from Senate Intelligence Committee chairman Dianne Feinstein, D-Calif., that she would hold hearings with intelligence and law enforcement officials on how the law is being carried out.
Wyden says that while there are numerous interpretations of how the Patriot Act works, the official government interpretation of the law remains classified. "A significant gap has developed now between what the public thinks the law says and what the government secretly claims it says," Wyden said.
Senate Judiciary Committee Chairman Patrick Leahy, D-Vt., while supporting extension of the Patriot Act measures, also pushed for changes to make the law more transparent, including requiring the Justice Department to periodically report to Congress on whether the powers in the law were being used properly.
Leahy had also sought to require the government to show greater evidence of a link with a terrorist threat when it asks for access to business records such as library circulation records or book seller records.
The Associated Press contributed to this report.