The original investigation by the special prosecutor was supposed to be about tracking down the source of the leak about Valerie Plame's CIA "covert" operatiave status to the press. (Remember the outrage of the left about Kenneth Starr's abuse of his power as special prosecutor during the Whitewater investigation? Remember the calls for the abolishment of the law allowing the creation of special prosecutors? Wonder what the left's stand is on this issue now?)
Rober Novak originally released the information about Valerie Plame, the non-covert covert agent. Novak originally got the information from Richard Armitage, the number two man in the State Department behind Colin Powell. Called to testify in the investigation, Scooter Libby could not correctly recall a conversation he supposedly had with some journalists years prior to the case.
The special prosecutor, Pat Fitzgerald, knows full well that the the "outing" of Plame wasn't actually a crime. Even though he knew that Armitage had outed her, and that Bob Woodward claimed to have had a conversation with Walter Pincus about Plame's CIA status, a conversation that Pincus denied, the only person indicted for lying was Scooter Libby.
Why Libby? Because Fitzgerald had to have a conviction on something in order to satisfy those on the left screaming for blood, and to salvage his own reputation. Libby was an obvious target because of his ties to the hated Dick Cheney.
Armitage was not indicted. Pincus wasn't indicted. The outing of Plame turned out not to have been a crime.
Scooter Libby, a man with the respect of many sensible politicos on both sides of the aisle, and a spotless record was indicted for nothing more than having a faulty memory.