Wasn't clear to Fitzgerald apparently.
I haven't read Fitzgerald yet...but he's been quoted as saying [paraphrase] that he's been very cautious and careful and making his charges, about which laws were broken. There are a lot of technical considerations.
Plame was an employee of the Counter Proliferation Division, a part of the Directorate of Operations, not the Directorate of Intelligence. She apparently had enough power to (possibly) send her husband on important missions. So she wasn't a janitor or clerk. Whether she is or was covert and what that means legally is still not absolutely clear.