And Marty Lederman comments:

John is testifying that his torture memos could have had no bearing on the abuse that took place in Iraq, because "the Geneva Conventions provided the relevant rules for the war in Iraq." There are several problems with this statement.

Most important is that OLC itself, when John was there, had advised the Pentagon that the Fourth Geneva Convention did not protect "unlawful combatants," which includes most if not all of the insurgents in Iraq.  (See page 4 of the April 2003 DOD Working Group Report.) ...

This explains why, according to several reports (most importantly those of Sy Hersh and Jane Mayer), the Pentagon and CIA placed Special Forces and CIA operatives in Iraq in 2001 or 2002, whose basic instructions were that there was no law -- certainly not Geneva -- that protected detainees, and that the "gloves were off" and that they could engage in widespread, wanton abuse and cruelty. Which they did.

(And as the Fay, Jones and Schlesinger Reports found, and many accounts attest, the conspicuous abuse by CIA and Special Forces in Iraq was an important contributing factor to the breakdown of ordinary norms among the regular military forces, as well.) The Pentagon and CIA would not have given these forces the green light to abuse prisoners if OLC had not previously advised that neither the Geneva Conventions nor any relevant statutes stood in the way of such abuse.

Finally, John's broad Commander-in-Chief override theory, which was a prominent part of the DOD Working Group Report, and which was briefed to General Miller on his way to "GTMOize" Iraq, obviously conveyed the message that the President could ignore any applicable statutes and treaties, even if they would otherwise apply.

John's legal advice, then, was a fairly direct cause -- certainly a necessary cause -- of the abuse in Iraq in 2002 and 2003.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.