Tom Maguire makes a compelling case that the CIA and Fitzgerald could not have missed in Plame's personnel files the record of her service abroad, critical to a determination as to whether there was the possiblity of an underlying crime in the Libby case and concealed that information.

[B]oth the CIA and the DoJ had access to Ms. Plame's file detailing her dates of service abroad, yet chose not to present that information to the defense.  Why might they do that?  A suspicious mind would wonder whether they would omit that data if it were helpful to their case, or only gloss past it if her most recent date of service abroad were say, 1997, when she was recalled to the United States (as per this Vanity Fair profile).

This is not right - our legal system has discovery rules for a reason.  IF Ms. Plame's formal dates for service abroad buttress the prosecution position, that should be disclosed to the defense so that they will not waste time pursuing a false trail, or so that the prosecution can prepare arguments that the CIA formal procedures do not comport with the language and intent of the IIPA.  On the other hand, if her formal dates for service abroad support the defense position, that should be disclosed so that the defense can argue that this represents the best established practice and settles the issue.

But it is simply not appropriate for Fitzgerald to unilaterally conceal this from the defense, especially when it is a reasonable guess that it was concealed because it would aid the defense.

Unfortunately, it is not as if Fitzgerald would never, uhh, shade his disclosures and filings - in the course of the Libby trial at least two transgressions were revealed: he had disclosed to the defense that John Dickerson of Slate may have received a Plame leak (from Ari Fleischer) but concealed the information that David Gregory of NBC News would have received the same leak at the same time.  And in the course of his legal maneuvering with Tim Russert, Fitzgerald failed to inform the court that Tim Russert (who was resisting a subpoena to testify) had already given evidence to DoJ investigators. 

Or for a more recent example of Fitzgerald's tactics, consider his recent sentencing memorandum.  Isikoff and Hosenball make much of the fact that "Patrick Fitzgerald has finally resolved one of the most disputed issues at the core of the long-running CIA leak controversy: Valerie Plame Wilson, he asserts, was a "covert" CIA officer".

But the defense response provided a bit of clarification which Fitzgerald had overlooked, or forgotten, or something:

The summary described above was provided to the defense along with a
companion summary that defined a "covert" CIA employee as a "CIA employee whose employment is not publicly acknowledged by the CIA or the employee."4 It is important to bear in mind that the IIPA defines "covert agent" differently.