Dan Froomkin at WaPo provides a compendium on pardonmania.
Personally, I think Patrick Fitzgerald, not being brain dead, took on his assignment as Special Counsel knowing full well from day one that a pardon would be a potential factor in his prosecutorial equation. And because he is good at his job, and mindful of the experience of Lawrence Walsh, he prepared for the possibility. And simply because a President has the power to grant a pardon does not mean that it couldn't be construed as a complicit act to further obstruct justice.
George Bush is foremost a coward, and I dare say he doesn't want to risk putting himself in legal jeopardy. Especially if he might have to contend with Patrick Fitzgerald.
Just pulling speculation outta my ass, but I wouldn't be surprised if Fitz already had a little conversation with Bush's attorney, Jim Sharp, to have him alert his client to the legal pitfalls of a pardon for Libby.
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