John Yoo is a former deputy assistant attorney general in the office of legal counsel of the Dept. of Justice. He wrote some of the memos in the new book The Torture Papers, including some pertaining to the Geneva Conventions and the definition of torture. He signed off on the memo denying prisoner-of-war status under the Geneva Conventions to al Qaeda and Taliban fighters in Afghanistan. Yoo is currently a professor of law at the University of California at Berkeley.