Henry Waxman, committee on oversight and government reform chair (emphasis added):
Rep. Waxman asks White House Chief of Staff Joshua Bolten to explain why the White House failed to conduct any investigation following the disclosure of Valerie Plame Wilson’s covert CIA employment. The letter follows the testimony of the Director of the Office of Security at the White House, James Knodell, that the White House Security Office did not follow the investigative steps prescribed by Executive Order 12958.
There was no investigation. Why would they perform one? It would just incriminate the president.
And just to clear up any mistaken ideas you might have about whether there was a crime committed, Rep. Waxman reports:
General Hayden and the CIA have cleared these following comments for today’s hearing. During her employment at the CIA, Ms. Wilson was undercover. Her employment status with the CIA was classified information, prohibited from disclosure under Executive Order 12958.
At the time of the publication of Robert Novak’s column on July 14, 2003, Ms. Wilson’s CIA employment status was covert. This was classified information.
And there you have it.