American guards arrived at the man's cell periodically over the next several days, shackled his hands and feet, blindfolded him and took him to a padded room for interrogation, the detainee said. After an hour or two, he was returned to his cell, fatigued but unable to sleep.

The fluorescent lights in his cell were never turned off, he said. At most hours, heavy metal or country music blared in the corridor. He said he was rousted at random times without explanation and made to stand in his cell. Even lying down, he said, he was kept from covering his face to block out the light, noise and cold. And when he was released after 97 days he was exhausted, depressed and scared.

[...] The detainee was Donald Vance, a 29-year-old Navy veteran from Chicago who went to Iraq as a security contractor. He wound up as a whistle-blower, passing information to the FBI about suspicious activities at the Iraqi security firm where he worked, including what he said was possible illegal weapons trading.

But when American soldiers raided the company at his urging, Vance and another American who worked there were detained as suspects by the military, which was unaware that Vance was an informer, according to officials and military documents.