While Professor Philip Zelikow maintains that the Bush Administration’s decision to use waterboarding and other brutal interrogation tactics was a policy mistake, it was more accurately a mistake of law. The distinction matters because labeling such conduct as policy leaves open the possibility that it could be revived by a future Administration. The fact that these tactics were illegal, and not just a poor policy choice, means that the officials and lawyers who authorized them need to be held accountable. Accountability need not come through a criminal trial, and could come in the form of a commission of inquiry, a congressional resolution, civil damage actions, or even bar discipline. Like interrogation, detention and targeting must also conform to law in the conduct of war, and must be sufficiently transparent to permit the public to assess the Administration’s claims of legality.