Rather than turn on him for betraying colleagues, most of the soldiers in his unit shook his hand. It was at home where the real trouble started.
Labelled a traitor
His wife had no idea that Mr Darby had handed in those photos, but when he was named, she had to flee to her sister's house which was then vandalised with graffiti. Many in his home town called him a traitor.
"I knew that some people wouldn't agree with what I did," he says.
"You have some people who don't view it as right and wrong. They view it as: I put American soldiers in prison over Iraqis."
That animosity in his home town has meant that he still cannot return there.
After Donald Rumsfeld blew his cover, he was bundled out of Iraq very quickly and lived under armed protection for the first six months.
He has since left the army but did testify at the trials of some of those accused of abuse and torture. It is Charles Graner he is most afraid of.
