Ethics

Via Volokh and Con Law Profs blog, here's the opinion mostly denying John Yoo's motion to dismiss claims by Jose Padilla.  I haven't had a chance to study the opinion in depth, but I'm particularly interested in the court's analysis of causation, which begins at page 31 of the opinion.  When I first read Padilla's complaint, it struck me that establishing causation might be difficult.  

UPDATE: The court ruled that at the pleading stage it will accept Padilla's allegations that Yoo "set in motion" a series of events resulting in deprivation of constitutional rights.  The defense argued that the decisions of Ashcroft and Bush effected the alleged deprivations, but the court's analysis turned on whether Yoo's alleged conduct played a substantial contributing factor.  Suppose that Yoo wants to adduce evidence on that point, that neither Bush nor Ashcroft can be forced to discuss their decision making process, and that Yoo claims his defense has been compromised.  Or suppose that Yoo wants to introduce documents in his defense and that the Obama administration decides not to declassify those particular documents.  (This could be so-called "graymail" but doesn't have to be.)  In those scenarios can Yoo argue that the claim must be dismissed?  Also, what proof would be necessary to survive a Rule 56 motion on the causation issue?