Punishing politically powerful criminals is about vindicating the rule of law. Partisan and political considerations should play no role in it. It is opponents of investigations and prosecutions who are being driven by partisan allegiances and a desire to advance their political interests. By contrast, proponents of investigations are seeking to vindicate the most apolitical yet crucial principle of our system of government: that we are a nation of laws that cannot allow extremely serious crimes to be swept under the rug for political reasons. That's true no matter what is best for Obama's political goals and no matter how many Democrats end up being implicated -- ethically, politically or even legally -- by the crimes that were committed.
For me, this has absolutely nothing to do with party. I'd be as insistent with any president who authorized torture of whatever party. And there is very good reason to believe that Pelosi knew a lot more than she has said. She should be investigated as well.