Hard Time

Orin Kerr links to a very interesting profile by the LA Times on Boalt Hall Law Professor (and former Bush administration attorney) John Yoo. Yoo was one of the chief architects of the infamous "torture memos," and thus has become a lightening rod of criticism. Regardless of what one thinks of him, however, it is apparent from the article that he is well-liked by colleagues and possesses a very sharp mind.

My question is this: let's assume for a moment that the policies Yoo outlined actually are illegal (I recognize this is quite controversial, so just accept it for the moment). Has Yoo conceivably done anything illegal? Does it depend on any particular variables, and if so, what? And of course the kicker, ought he be held accountable in the event that his suggestions advocate breaking the law?

Any legal professional more educated than I am, please feel free to chime in a response.