Fitzgerald had “issues” with Scooter Libby over the Marc Rich pardon. Libby was Rich’s lawyer and Fitzgerald was mightily steamed when Clinton pardoned him.
Although Fitzgerald is a Democrat, he was nominated by Peter Fitzgerald (a conservative/libertarian) US Senator from Illinois because of his generally non-partisan behavior. My best guess is that Fitz suffers from overzealous prosecution complex (i.e., wanting to justify his position) rather than raw partisanship.
For the sake of further irony, guess who took Peter Fitzgerald’s Senate seat after he declined to run again. Yup, it was The Won.
Yep, and I don't know that I can ever forgive Peter Fitzgerald for that, as his refusal to run ultimately gave us Zero.