WASHINGTON — The Senate gave final congressional approval on Friday to a bill renewing the government’s authority to monitor overseas phone calls and e-mails of suspected foreign spies and terrorists — but not Americans — without obtaining a court order for each intercept.
The classified Foreign Intelligence Surveillance Act program was scheduled to expire by year’s end. The 73-to-23 vote sent the bill to a supportive President Obama, whose signature would keep the warrantless intercept program in operation for another five years.
The Senate majority rejected arguments from an unusual combination of Democratic liberals and ideological Republican conservatives, who sought to amend the bill to require the government to reveal statistics showing whether any Americans were swept up in the foreign intercepts. The attempt lost, with 52 votes against and 43 in favor.
The Obama administration’s intelligence community and leaders of the Senate’s intelligence committee said the information should be classified and opposed the disclosure, repeating that it is illegal to target Americans without an order from a special US surveillance court.
The group seeking more disclosures also sought — unsuccessfully — a determination by the government of whether any intelligence agency attempted to use information gained from foreigners to search for information on Americans without a warrant, referred to as ‘‘back-door’’ searches.
The prohibition against targeting Americans without a warrant protects Americans in the United States and abroad.
After the bill was approved, Justice Department spokesman Dean Boyd said communications collected under the program ‘‘have provided the intelligence community insight into terrorist networks and plans’’ and have ‘‘directly and significantly contributed to successful operations to impede the proliferation of weapons of mass destruction and related technologies.’’
Boyd said intercepted communications also revealed potential cyberthreats against the United States, including specific potential computer network attacks.
The debate focused on the need to balance national security with civil liberties. Senators Dianne Feinstein, Democrat of California, and Saxby Chambliss, Republican of Georgia,the chairwoman and top Republican on the Senate Intelligence Committee, warned that the classified intercept program would be jeopardized if even statistical information was disclosed.
They sparred repeatedly with Senator Ron Wyden, Democrat of Oregon, who held the bill up for months until he was allowed to argue on the Senate floor that Americans’ civil liberties were in danger under the law.
During debate that began Thursday, Feinstein bluntly told Wyden, a fellow liberal, that she opposed his disclosure amendment because, ‘‘I know where this goes. Where it goes is to destroy the program.’’
Wyden insisted his group was interested only in making public government estimates that already existed. In insisting on information about whether the foreign intercepts led to warrantless ‘‘back door’’ searches of Americans, the senator said there already had been one instance of such a violation.
He said the finding of a violation, details of which remain classified, ‘‘demonstrates the impact of the law on Americans’ privacy has been real and is not hypothetical.’’
‘‘How many phone calls to and from Americans have been swept up in this authority?’’ he asked.
A member of the Intelligence Committee, Wyden said he was trying to ‘‘strike a balance between security and liberty’’ and that ‘‘the 300 million Americans who expect us to strike that balance . . . are in the dark.’’
When Americans are targeted for surveillance, the government must get a warrant from a special 11-judge court of US district judges appointed by the Supreme Court. In contrast, when foreigners abroad are targeted, the surveillance court approves annual certifications submitted by the attorney general and the director of national intelligence that identify certain categories of foreign intelligence targets.
The House in September approved the same five-year extension of the law by a vote of 301 to 118.
Feinstein said the surveillance law has procedures to restrict use of information on Americans that is inadvertently captured in the intercepts.
She said there were 100 arrests in terrorism cases between 2009 and 2012, some of them as a direct result of the surveillance program.
The Senate Judiciary Committee chairman, Senator Patrick Leahy, Democrat of Vermont, tried to substitute a three-year extension of the law instead of five, but the proposal was defeated, with 52 votes against and 38 in favor.