The soldier accused of being the ringleader in the abuse of prisoners at Iraq's Abu Ghraib jail has been found guilty of mistreating detainees.
Spc Graner did not testify during the four-day trial
Charles Graner, 36, was convicted by a military jury in Texas after a four-day trial at which he was said to have assaulted prisoners for fun.
The 36-year-old had pleaded not guilty to five charges, with the defence arguing that he was following orders.
He now faces up to 15 years in a military prison.
The 10-person jury took less than five hours to reach their verdict.
Before it retired, prosecutor Capt Chris Graveline told the jury of a series of incidents of abuse, and showed them photographs and video taken inside the prison in November 2003.
The publication in early 2004 of dozens of photographs showing prisoner abuse at Abu Ghraib prompted global condemnation of US actions in Iraq.
The pictures led to accusations of prisoner abuse at a string of US detention centres in Iraq, Afghanistan and at Guantanamo Bay, Cuba.
Senior military and political figures, including US Defence Secretary Donald Rumsfeld, were alleged to have known of the abuses.
An independent commission ruled in August 2004 that blame for the abuses lay almost totally with the soldiers who ran the jail, but faulted Mr Rumsfeld and colleagues for not providing adequate leadership to prevent the abuse.
Among other things, Specialist Graner was accused of stacking naked detainees in a human pyramid, and later ordering them to masturbate while other soldiers took photographs.
The court was told that he punched one man in the head hard enough to knock him out and beat an injured prisoner with a collapsible metal stick.
"It's all about their own sexual, depraved humour," Capt Graveline told the court, at the Fort Hood US army base in Texas.
"They decided for their own amusement to assault, degrade."
Civilian defence lawyer Guy Womack countered that his client and other guards were following a "persistent, consistent set of orders to soften up the detainees, to do things so we can interrogate them successfully in support of our mission".
He described the notorious photos taken inside the prison as "gallows humour" resulting from unrelenting stress felt by the guards.
He also suggested that Spc Graner and the other low-level guards were scapegoats, put on trial to protect more senior army officers.
The defence lawyer said there was nothing wrong with stripping the prisoners, whom he described as "hardened terrorists", and stacking them into a pyramid to control them.
"They did it in a safe manner so nobody would get hurt... If there was anything wrong, it was that they took a picture and they were smiling," Mr Womack said.
The trial included testimony from three guards who had made plea deals with prosecutors.
Two other guards are awaiting trial, as well as Private Lynndie England, a clerk at Abu Ghraib who last year gave birth to a baby believed to have been fathered by Spc Graner.