Tony Diaz, a former military-police sergeant who served at Abu Ghraib, stares into Errol Morris' camera and speaks in baffled tones about being called into a shower room at that notorious Baghdad prison where CIA interrogators were beating an Iraqi detainee to death. Diaz says he did not participate in the man's interrogation and did not beat him; he was ordered to hold the man up and help secure his arms, and he followed those orders. While he was doing that, drops of blood fell from the detainee's battered face onto Diaz's uniform, and that troubled him. He hadn't done anything wrong, he told Morris, yet the blood made him feel responsible.

I don't mean to demonize Tony Diaz. Virtually alone among the interviewees in Morris' new film "Standard Operating Procedure," an artful, meditative investigation of the infamous Abu Ghraib photographs and the circumstances that produced them, Diaz seems to be wrestling with his conscience, after his own bewildered and evasive fashion. (Morris has also co-authored a book of the same title with New Yorker staff writer and Paris Review editor Philip Gourevitch, to be published next month.)

» Continued