Sources said the materials were technically classified but not highly sensitive.

CNN: STORY HIGHLIGHTS

Former Vice President Dick Cheney's chief of staff, Lewis "Scooter" Libby, was convicted in 2007 in connection with the leaking of CIA officer Plame's identity -- information that was technically classified, though Cheney later implied that information had been declassified.

CNN: Holder assigns prosecutors to investigate leaks

Because many things everybody knows about are technically secret, creating an arbitrary, ever-shifting line between the classified and the public domains.

FORBES: The Government's Not-Secret Secrets