My primary caution is, as I described before, that we need to leave "room to be wrong" in order to get decent people engaged in government service, to explore different ideas, to not be so tentative and cautious as to be ineffective. But there are two other ideas I'd like to throw out there.
First, there is the historical problem of having people of one Administration prosecute people from the immediate past Administration for what turn out to be bad policies, bad ideas, bad decisions, and the like. Even if these are shockingly unethical (as torture surely is) there is value and stability to be had from leaving the past in the past.
The threat of prosecution for what had been done in his about-to-end term of office was the basic problem facing Julius Caesar. He found a solution. It is not one I would welcome in the present day.
The other issue is related to the phenomenon I described recently with respect to the Miss USA/SSM issue a few days ago. If you push too hard on a touchy social issue, you create backlash. Now, there are a lot of folks who have drunk of the red variety of Kool-Aid out there. They are already warm to the idea of torturing bad guys, deny that waterboarding is torture at all, and will call you a traitor if you disagree with them. If we prosecute the torture lawyers for setting in motion a chain of events that led to people within our power being tortured, we run the risk of encouraging these sorts to look to the torture lawyers as heroes, as models of conduct for others to follow, and for reflexively assuming that whatever it was these guys did enjoys moral justification. The last thing we want is to drive the debate on this issue into ground where those kinds of issues are up for serious debate.
But "leave well enough alone" is a prescription for injustice and the perception that this sort of behavior is, in fact, tolerable. Which it is not. I'm starting to warm to the idea of a truth commission more than I had been over the last week.