WASHINGTON — The government does not need a search warrant when it taps the phones or checks the e-mails of suspected terrorists who are outside the U.S., even if Americans may be overheard on the calls, a special intelligence court ruled in an opinion released Thursday.
The decision confirms what Bush administration officials and some legal experts have long argued. Although the Constitution protects the privacy rights of Americans against "unreasonable searches and seizures," this principle does not bar U.S. spy agencies from conducting surveillance aimed at foreign targets abroad.
The opinion, combined with the arrival of the Obama administration, may quell some of the controversy over wiretapping.
In 2005, President Bush reluctantly admitted he had authorized the National Security Agency to intercept international phone calls -- without a warrant -- in the hunt for possible terrorists. The move appeared to violate the 1978 Foreign Intelligence Surveillance Act. The Cold War-era measure allowed government spying in the U.S., but only if agents obtained a warrant from a special court within the Justice Department.
Bush's order went largely unchallenged in the courts for a technical reason: No plaintiff could show he or she had been wiretapped; therefore, no one had standing to sue.
But last year, Democrats and Republicans agreed to update the law that regulates intelligence gathering. The new era of satellite communications meant, for example, that some overseas calls were routed through U.S.-based telephone companies.
Lawmakers said, and the Bush administration agreed, that the government needed a warrant before it intercepted phone calls in this country. Agents must show the target is linked to a foreign country or a terrorist group. But the new law also made it clear that the government could target suspicious people "reasonably believed to be outside the United States" and listen to their calls without a warrant.
The opinion released Thursday determined the Constitution did not demand the use of warrants when the government was targeting overseas calls.
There are two reasons for making an exception to the normal requirement of a search warrant, the court said. One is that intelligence gathering, not building a criminal case, is involved. And the other is that the targets are outside the U.S.
"We hold that a foreign intelligence exception to the 4th Amendment's warrant requirement exists when surveillance is conducted to obtain foreign intelligence for national security purposes and is directed against foreign powers or agents of foreign powers reasonably believed to be located outside the United States," the court said.
The opinion said the government was required to minimize or block out the parts of wiretaps that included Americans. "The government assures us that it does not maintain a database of incidentally collected information from non-targeted United States" residents overheard on the international calls, the ruling said.
The Justice Department said it was pleased the ruling had confirmed the constitutionality of the foreign surveillance.
The American Civil Liberties Union criticized the ruling and said it could leave Americans vulnerable to having their calls monitored. "The government should not be able to nullify 4th Amendment rights simply by invoking national security," said Jameel Jaffer, director of the ACLU's National Security Project.