This segment was originally broadcast on Dec. 10, 2006. It was updated on June 21, 2007.
You may not remember the name Joe Darby, but you remember the impact of what he did. Darby turned in the pictures of prisoner abuse at Abu Ghraib in Iraq - pictures he had discovered purely by accident. Unfortunately for Darby, exposing the truth has changed his life forever, and for the worse.
60 Minutes first broadcast this story last December, the story of an ordinary Joe who grew up in Appalachia and signed up to be an MP in the Army Reserves. As CNN's Anderson Cooper reports, Darby's local unit was sent to Abu Ghraib where he worked in the office while others guarded the prisoners.
And then one day, when Joe Darby wanted scenic pictures to send home, he spotted the unit's camera buff, prison guard Charles Graner.
"So I walked up to Graner and I, you know, 'Hey do you have any pictures?' And he said 'Yeah, yeah, hold on.' Reaches into his computer bag and pulls out two CDs and just hands them to me," Darby remembers.
Asked if he thinks Graner realized what was on these discs, Darby says, "I don't think he realized what was on, but I don't think it would have mattered either way. I knew Graner and Graner trusted me."
That trust was about to change Darby's life forever. He copied Graner's discs and gave him back the originals. Later, when Darby looked at the photos he first saw scenic shots of Iraq, but then he came upon the pictures that launched the scandal. One of the first shots was a photo of a pyramid of naked Iraqis.
"I didn't realize it was Iraqis at first, you know? 'Cause we lived in prison cells too," Darby says.
At first, Darby thought the pictures were maybe of American soldiers goofing off.
"I laughed. I looked at it and I laughed. And then the next photo was of Graner and England standing behind them. And I was like, 'Wait a minute. This is the prison. These are prisoners.' And then it kind of sunk in that they were doing this to prisoners. This was people being forced to do this," Darby recalls.
Forced, Darby said, by Graner, who he called the ring leader.
Asked what Charles Graner was like, Darby says, "If you were around him long enough you saw that he had a dark side, a morbid side."
And a sadistic side, according to Darby, who told 60 Minutes Graner directed the abusive posing and picture taking during his night shift when he and his buddies were alone with the prisoners.
What was going through his mind when he clicked through the photos?
"Disbelief," Darby says. "I tried to think of a reason why they would do this, you know."
"Well there's some who say, 'Look, this is a valuable interrogation tool,'" Cooper remarks.
"These were MPs. Our job wasn't to interrogate prisoners," Darby says.
"There has been testimony that some of the MPs were told to soften the prisoners up, that this was part of that," Cooper says.
"And I've heard that. And I wasn't there. I didn't work the tier. I can't say that that didn't happen," Darby replies.
But no matter why they were doing it, Darby knew what they were doing was wrong.
"I've always had a moral sense of right and wrong. And I knew that you know, friends or not, it had to stop," Darby says.