© Patrick Semansky/Associated Press
National security officials have argued that such surveillance is lawful and helpful in identifying people who might have links to terrorism, espionage or otherwise are targeted for intelligence-gathering. The fact that the sender of such a message would know an email address or phone number associated with a surveillance target is grounds for suspicion, these officials argued.
The decision is a major development in American surveillance policy. It brings to an end a once-secret form of wiretapping that privacy advocates have argued overstepped the Fourth Amendment's ban on unreasonable searches — even though the Foreign Intelligence Surveillance Court upheld it as lawful — because the government was intercepting communications based on what they say, rather than who sent or received them.
Senator Ron Wyden, an Oregon Democrat who has long been a critic of N.S.A. surveillance, said that he would introduce legislation codifying the new limit. The law that authorizes the program, the FISA Amendments Act, is up for renewal at the end of 2017.
"This change ends a practice that allowed Americans' communications to be collected without a warrant merely for mentioning a foreign target," Mr. Wyden said. "For years I've repeatedly raised concerns that this amounted to an end-run around the Fourth Amendment. This transparency should be commended."
The existence of this so-called "about the target" collection was first reported by The New York Times in 2013.
The N.S.A. made the change to resolve problems it was having complying with special rules imposed by the surveillance court in 2011 to protect Americans' privacy. For technical reasons, the agency ended up collecting messages sent and received domestically as a byproduct of such surveillance, the officials said.
The problem stemmed from certain bundled messages that internet companies sometimes packaged together and transmitted as a unit. If even one of them had a foreign target's email address somewhere in it, all were sucked in.
After the N.S.A. brought that issue to the court's attention in 2011, a judge ruled that it violated the Fourth Amendment, which bars unreasonable searches. The agency then proposed putting the bundled messages in a special repository to which analysts, searching through intercepts to write intelligence reports, would generally not have access. The court permitted that type of collection to continue with that restriction.
But last year, officials said, the N.S.A. discovered that analysts were querying the bundled messages in a way that did not comply with those rules. The agency brought the matter to the court's attention, resulting in a delay in reauthorizing the broader warrantless surveillance program until the agency proposed ceasing this collection practice.
This isn't enough to party about folks. Only emails about foreign targets. Otherwise everything else is open season. Besides, how does anyone know if anything ceases? They are pathological and professional liars. As long as they still exists, they can't be believed.