** FILE ** I. Lewis “Scooter” Libby, Vice President Dick Cheney’s chief of staff, testifies on Capitol Hill in this March 1, 2001 file photo in Washington. Top presidential political adviser Karl Rove and Vice President Dick Cheney’s chief of staff, I. Lewis “Scooter” Libby, have emerged as central figures in the CIA leak investigation because they had contacts with reporters who learned Plame’s identity or disclosed it in news stories. (AP Photo/Joe Marquette)