WASHINGTON - The US government spied on electronic communications between Americans with no links to terror suspects until a judge ruled it illegal in 2011, officials acknowledged Wednesday.
Under pressure from a lawsuit and accusations of excessive secrecy, the government chose to reveal the practice in declassified documents from the Foreign Intelligence Surveillance Court, which reviews the legality of eavesdropping programs.
The violation of laws prohibiting domestic spying involved tens of thousands of emails and other electronic communications among Americans, according to the court papers released by President Barack Obama's administration.
The court's opinions are usually kept secret. But the government chose to release the documents as it faces a Freedom of Information lawsuit and mounting criticism over sweeping surveillance operations, following bombshell leaks from former US intelligence contractor Edward Snowden.
Officials said the court rulings had been declassified to better inform the public about how the eavesdropping programs are carried out with what they called rigorous oversight.
In his ruling, Judge John Bates blasted the NSA over the breach of privacy and called it part of a pattern in which the court was mislead by the agency with regard to the nature of surveillance activities.
"The court is troubled that the government's revelations regarding NSA's acquisition of Internet transactions mark the third instance in less than three years in which the government has disclosed a substantial misrepresentation regarding the scope of a major collection programme," the judge wrote.
Under the programme addressed by the court in 2011, the NSA had diverted a massive trove of international data flowing through fiber-optic cables in the United States, purportedly to sift through foreign communications.