Shore said Sergeant 1st Class Trey Corrales had ordered him to kill the Iraqi who was suspected of firing at a US helicopter.

Corrales, charged with premeditated murder, will go on trial on April 22.

Colonel Donna Wright, who presided over Shore's trial, told jurors they could either convict Shore of the murder charge, which is the equivalent of manslaughter, or of aggravated assault, or they could find him innocent.

Captain James Leary, the prosecutor, said duress was not a defence for murder, adding that a witness testified to seeing the victim talking and moving before he was shot.

He said that although Shore may not have wanted to hurt the victim, the decision to fire two shots at the man was itself illegal.

'Sloppy investigation'

Mike Waddington, Shore's lawyer, described the investigation as "sloppy", saying investigators initially went to the wrong house and excavated the wrong yard.

"Why would a young soldier stand there?'' he asked. "Perhaps terror. He wouldn't have shot but for fear."

Reading out the testimony of Essa Ahmed, a translator with Shore's unit during the raid, he argued that Shore had acted under pressure and had reason to fear Corrales would attack him if he did not follow orders.

Waddington also said that the prosecutor had not produced any physical or forensic evidence that could link Shore to the killing, and that US authorities had not identified the dead Iraqi.