California ? A military judge granted a Marine corporal’s request Thursday to withdraw his guilty plea to charges of murdering an unarmed Iraqi civilian, but warned the serviceman that he could be sentenced to death if convicted.

Cpl. Trent Thomas, 25, pleaded guilty as part of a pretrial agreement Jan. 18 to several charges, including kidnapping and murder, in the slaying of 52-year-old Hashim Ibrahim Awad last year in Hamdania. But Thomas said Thursday that he no longer believes he’s guilty and was following a lawful order.

“Sir, when my country gives me an order, I follow it,” Thomas told the judge, Lt. Col. Tracy A. Daly, adding that the order came from his squad leader, Sgt. Lawrence Hutchins III, and higher up the chain of command.

Thomas, of Madison, Ill., was one of a squad of seven Marines and a sailor accused last year of hatching a plot to kill an Iraqi in the town of Hamdania. Four others pleaded guilty to lesser charges. Thomas, the squad’s second in command, could face life in prison.