It is time for a constitutional amendment to rein in criminal presidents: The classic examples are the Presidents Bush who have had the gall to do what Nixon had the decency not to try. An amendment preventing presidents from using the pardon power to protect their criminal co-conspirators.
HW used his pardon power to prevent the independent prosecutor from closing in on his own crimes in Iran-Contra. W has already shielded Scooter Libby from the consequences of his crimes and prevented any further investigation of his administrations treasonous exposure of Ms. Plame.
The founding fathers left a loophole here. They apparently thought that Congress would use impeachment more and prevent this. There is a reference, that I'm still looking for (I think think in the Federalist papers) that pardons that Presidents issue to subordinates protect themselves from criminal investigation would be invalid.
I propose an amendment prohibiting any President from pardoning any political appointee from his administration. Alternately one could require that all pardons be approved by a majority of both houses of Congress. The founding fathers considered the latter option, but decided on a more unlimited power. We can't stop W from abusing his magic wand before he leaves office, but we can stop future W's. The example of the Bush clan is deeply corrosive to democracy. It must stop now.
As a side question to the lawyers... If Bush tries to pardon himself out of War Crimes trials in the US, would international law allow him to be charged outside the US? Could we even extradite him to the Hague?