Just like the IRS can't -
Oh wait...
“Oh wait...”
That’s just the point where the brits come into the game.
The NSA is allowed to gather data about us citizens. They’re not allowed to examin that data. BUT: The NSA is allowed to forward ALL gathered information to the british MI5. The MI5 examines that data on demand by the NSA. The perfect legal loop hole ....
There is an article on Drudge that I haven’t read yet, that says that the FISA courts do not follow the law, they are above it.