A Marine went on trial Monday on charges he delivered a karate kick to the chest of an Iraqi prisoner who authorities say later suffocated from a crushed windpipe.

The assault case against Reserve Sgt. Gary Pittman is the first court-martial known to be connected to the death of a prisoner in Iraq.

The POW, Nagem Sadoon Hatab, had been rumored to be an official of Saddam Hussein's Baath Party and part of the ambush of a U.S. Army convoy that left 11 soldiers dead and led to the capture of Pfc. Jessica Lynch and five others.

Within 48 hours of the Iraqi's arrest in June 2003, a guard found a lifeless Hatab lying naked and covered in his own waste in a yard at Camp Whitehorse, a makeshift lockup outside Nasiriyah that has since been closed.

According to a fellow Marine who has been granted immunity, Pittman karate-kicked the handcuffed, hooded Hatab in the chest so hard that he flew three feet before hitting the floor.

An autopsy concluded that Hatab had seven broken ribs and slowly suffocated from a crushed windpipe. Defense lawyers say Hatab died of natural causes, perhaps from an asthma attack.

On Monday, the judge in the case, Col. Robert Chester, agreed to let a doctor testify for the defense that the markings on Hatab's body were not consistent with a kick to the chest.

Pittman, who in civilian life was a guard at a federal prison, is one of three men charged in Hatab's death. Eight Marines originally were charged with crimes ranging from dereliction of duty to negligent homicide. However, a judge ruled that it could not be determined who caused Hatab's death.

Pittman could get more than three years in a military prison if found guilty of assault and dereliction of duty.