US Army sergeant convicted of murdering four Iraqi detainees
Prosecutors told a court martial in Germany on Wednesday that Master Sgt John Hatley acted as "judge, jury and executioner" of the four men, captured in the Baghdad area in the spring of 2007.
After Hatley's unit was engaged in an exchange of fire, the men were seen fleeing a building which was found to contain assault rifles, grenades and sniper rifles.
The court martial heard that the four were not going to be prosecuted due to lack of evidence and would normally have been set free.
Two other soldiers, who have already been found guilty of the killings, testified that the prisoners were instead taken to a deserted site near a canal in Baghdad's West Rasheed neighbourhood.
There, they were shot point-blank in the back of the head with automatic pistols.
Captain Derrick Grace, prosecuting, said that evidence had pointed to "a complete breakdown of discipline and crimes that are among the worst of a soldier".
Hatley, 40, the most senior rank of the trio, had denied charges of premeditated murder and conspiracy to commit premeditated murder.
He was acquitted of involvement in a shooting earlier that year of a wounded detainee who medics said was close to death.
Prosecutors said Hatley oversaw the shootings of the detainees and had told his comrades they were going to "take care" of the Iraqis.
Defence lawyers claimed that there was no physical evidence that the shootings ever took place.
An eight-man military jury heard from a string of witnesses who testified to Hatley's leadership and personal qualities.
However, Capt Grace argued that "good soldiers don't murder people", adding that the prisoners were "zip-tied, blindfolded and stationary".
Hatley, a career soldier who has served in the first Gulf War, Kosovo and in Iraq, will be sentenced on Thursday at the army's Rose Barracks in southern Germany. He faces the possibility of life in prison without parole.
All three soldiers were at the time with the 1st Battalion, 18th Infantry Regiment, in Baghdad.