Sgt Ryan Weemer left the marines and applied to join the Secret Service
A US military jury has acquitted a marine sergeant of killing an unarmed detainee during fighting in Iraq.
Sgt Ryan Weemer's court-martial was sparked by his own alleged confession to the 2004 killing in Falluja during a lie-detector test.
The jury of eight US marines also cleared him of dereliction of duty.
The 26-year-old could have faced a maximum sentence of life in prison and a dishonourable discharge if had been convicted of murder.
After the verdict was read out, Sgt Weemer hugged and thanked his lawyer while members of his family wept with relief in their front-row seats.
The court-martial, at Camp Pendleton marine base in California, had heard that Sgt Weemer had left the Marine Corps and applied for a post in the Secret Service in 2006.
But during a polygraph test as part of his application, he said he had killed an unarmed captive in Iraq in 2004.
That led to a criminal investigation and he was recalled to active duty to face military prosecution.
Sgt Weemer's defence argued that prosecutors could not prove he killed the unarmed captive because there were no bodies, no relatives complaining of lost loved ones and no forensic evidence.
Sgt Weemer's squadron leader, Jose Nazario, has already been tried and found not guilty.
Military officials say a third marine, Sgt Jermaine Nelson, is also facing a court-martial over the incident, but no date has been set.