The Electronic Privacy Information Center Friday asked Congress to begin a series of oversight hearings on whether the National Security Agency's telephone surveillance scheme was legal.

 A letter from the group says a secret court "went beyond its legal authority when it sanctioned a program of domestic surveillance unrelated to the collection of foreign intelligence."

The disclosure of the court order, which The Guardian newspaper did late Wednesday, has roiled Washington, D.C. officialdom -- but most of the debate has centered on the political fallout, not whether the Foreign Intelligence Surveillance Court order was legal or not. A series of congressional hearings could shift the debate to whether the Justice Department and the court's judges complied with the law or not.