I'm not familiar with US law, but the appointment of a "Special Prosecutor" in the Clinton era seemed pretty effective -if totally partisan.  However the appointment by congress of such a prosecutor with extensive powers and resources should keep the GOP criminals busy tying to defend themselves for the next 4 years whilst keeping the whole process at arms length from the Obama administration itself.  

Keeping the GOP on the defensive seems a reasonable political strategy whilst at the same time having all the benefits of reasserting the rule of law.

Obama should go further than just joining the ICC - he should promulgate a Treaty requiring all UN member states to extradite their citizens to appear before the Court.  Otherwise no powerful US citizen will ever appear before the court in any case.

This is one of those issues where Congress will have to take a lead however.  It has to make Obama do it to make it appear he is not acting in a partisan fashion.

notes from no w here