Behenna was later told to take Mansur back to his village, but Behenna instead took him to a remote area, ordered him to strip naked and then questioned him at gunpoint. Behenna shot Mansur twice, killing him.
He testified at his court martial that he shot Mansur in self-defense after Mansur threw a piece of concrete at him and lunged for his gun.
Behenna was originally charged with premeditated murder in a combat zone but was convicted of unpremeditated murder in a combat zone.
Scott Behenna, a former investigator for the OSBI who now works as an intelligence analyst for the FBI, said prosecutors presented no physical evidence to support their claim that Mansur was seated when Michael Behenna shot him.
Michael Behenna's conviction has been upheld by two military appeals courts. Attorneys for Behenna have asked the U.S. Supreme Court to review his case.
Should the court decline to hear that appeal, which seems likely given the small percentage of cases taken by the high court, Behenna's only option for a reduced sentence will lie with the U.S. Army Clemency and Parole Board. That board already has given Behenna a five-year reduction; his parents are planning to seek another reduction at a hearing in early February.
The board also heard Tuesday from the heads of the legal branches for the U.S. Army, Marines and Air Force.
Lt. Gen. Dana K. Chipman, the judge advocate general for the U.S. Army, said he welcomed the board's review and suggestions but cautioned against any changes that might recalibrate the system.
“We must always be conscious that a slight adjustment to a system of justice could inadvertently tip the scale in one direction or the other,” Chipman said. “For that reason, adjustments to a code of justice that may deprive an American of his liberty must be done carefully and deliberately.”