Some people might be willing to look the other way on the NSA's data mining, because they trust the American government to do the right thing with our information. But do they also trust the British government? Coming on the backs of The Washington Post's exposure of the PRISM program, The Guardian in the U.K. now reports that the Government Communications Headquarters (GCHQ), which is England's equivalent of the NSA, has had access to the same system and has generated hundreds of intelligence reports using the Americans' data.
One of the key principles of PRISM (at least according to the people that created it) is that it is designed to intercept "foreign" communications that happen to get routed through the equipment of U.S. tech companies — even though, in practice, it collects everything and only allows analysts to search for foreign intelligence. But those searches are based on a 51-percent "confidence" level that data came from an outside source, which basically guarantees that they get just as much domestic intel as foreign. They aren't supposed to use the American info that accidentally gets sucked in, but it's apparently "nothing to worry about" if they do.
Except, well, the U.K. also has its own rules about gathering intelligence, and GCHQ can't just grab anything it wants from foreign sources. If one of their own investigations leads to say, a Gmail account based in America, they must make a lengthly formal request through the U.S. Justice Department to gain access from Google. (That's something they do a lot; almost 3,000 times for Google alone last year.) However, according the Guardian, they can also go straight to PRISM, bypassing the normal legal procedures. GCHQ even has a special department set up just to process material from PRISM.
The British agency reportedly created 197 intelligence reports based on the U.S. program in 2012, but has had access to system for more than three years. Those reports are also passed on to the British intelligence agencies, MI-5 and MI-6. So it seems lines between foreign and domestic and secrecy and privacy are even blurrier than you realized.