A US marine has been found guilty of kidnapping and conspiring to murder an Iraqi civilian shot dead during an overnight raid near Baghdad last year.
A squadmate said Cpl Thomas was a key player in the event
Cpl Trent Thomas was the first of eight members of an infantry unit to go on trial for the killing of Hashim Ibrahim Awad, 52, in Hamdaniya in April 2006.
The Purple Heart recipient, who was acquitted of premeditated murder, faces a maximum sentence of life in prison.
Cpl Thomas withdrew his plea of guilty in February after having an "epiphany".
The decision was based on a belief that he had lawful authority for his actions.
At the court martial, several members of Cpl Thomas's unit testified that their squad leader, Sgt Lawrence G Hutchins III, had hatched a plot to kidnap and kill a suspected insurgent from his house in Hamdaniya.
When the unit failed to find their target, Cpl Thomas allegedly led a four-man team that entered Mr Awad's house, abducted him and took him to a ditch.
Sgt Hutchins then fired three shots into Mr Awad's head followed by at least seven more rounds to the head from Cpl Thomas, the court heard.
The troops later placed a rifle and shovel by his body to make it seem as if he had been an insurgent planting a roadside bomb.
The marine's defence team argued he was following the orders of Sgt Hutchins.
"Sir, when my country gives me an order, I follow it," he told the court when changing his plea in February.
His lawyer also said his judgement had been affected by a traumatic brain injury caused by exposure to more than 25 bomb blasts during his three tours of duty in Iraq.
Five other members of the unit - four marines and a Navy medic - pleaded guilty to reduced charges before the trial and were sentenced to between one and eight years in prison.
Sgt Hutchins and Cpl Marshall L Magincalda will face courts martial over the next week.
The case is one of several in which US troops are accused of killing Iraqi civilians.