Nick Merrill: the man who may unlock the secrecy of the FBI's controversial subpoenas

27 November stands to mark a victory a decade in the making for Merrill, who was served with a national security letter in 2004 and said he was 'terrified' of revealing the extent of the information he was being asked to hand over

For over a decade, Nick Merrill could say nothing about the FBI subpoena he received in 2004 - not to his wife, his ailing father nor his closest friends. Merrill didn't even know if consulting an attorney about it would land him in a jail cell.

But now, after more than a decade of court challenges, Merrill is on the verge of revealing an unprecedented amount of detail about what the FBI and its partner agencies believe they can obtain without a warrant, using a controversial form of nonjudicial subpoena called a national security letter (NSL).