A skeptical observer could say that;
Libby’s motivation to lie was to protect someone higher up (or the administration).
Libby threatened to expose that person (or the administration) if he went to prison.
That ‘higher up’ arranged for Libby’s sentence to be commuted to protect themselves (or the administration).
Either way, it appears (to the outside observer) that US ‘justice’ is based not on the decision of the courts, but by whom you know.
Hilton can get out because the bars don’t go with her outfit.
Libby can lie to a grand jury and get away with a slap on the wrist (the fine is nothing compared to the amount he earns).
This seemed a balanced view of the result;
Washington Post: Will Libby get a pardon?
Jeralyn Merritt: That is anyone's guess. Mine would be that if Libby maintains his silence and stoically goes off to do any sentence the judge imposes, he will get one before Bush leaves office. But, that's a political opinion, not a legal one.