A tribunal in London has ruled that the United Kingdom's mass surveillance of cellphone and online communications violated human rights.

NPR's Ari Shapiro reports that the government had already tweaked the program in response to concerns.

Ari filed this report for our Newscast unit:

"The Investigatory Powers Tribunal was established in 2000 and this is the first time it has upheld a complaint about British intelligence agencies."For years, America's National Security Agency has intercepted communications from people around the world including in the U.K."British spy agencies used some of the information that the NSA intercepted from the U.K."The tribunal says that information sharing violated the European convention on human rights — specifically, parts of the convention relating to privacy and freedom of expression."The existence of this information-sharing program only came to light because of documents revealed by NSA leaker Edward Snowden."

The New York Times spoke to Ian Brown, a professor of information security and privacy at the University of Oxford. He told the paper this was a "landmark case," but things may not change all that much.

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