The answer to my earlier question is: Deputy U.S. Attorney General James Comey.
According to this CNN report on December 31, 2003, U.S. Attorney General John Ashcroft recused himself from the Plame investigation. Comey became the acting attorney general for this case, and immediately appointed Patrick Fitzgerald as special prosecutor for the investigation.
So now the question becomes: who is James Comey?
See, this is the type of question an average bird like me asks today. A Washington insider or, like, an actual professional journalist would already know this and may not think to inform the rest of us. So this is a service I can provide.
Aha! Apparently I'm not the only one asking this question today. Here's a profile of Comey, which incidentally also provides insight into Comey's "close friend and colleague" Patrick Fitzgerald. The last line is what I found to be most interesting and encouraging about both men: "If it's a politically charged issue, he (Comey) will call it straight," Fitzgerald said. "At the end, he'll walk out with his integrity."