Wearing his desert camouflage uniform, Staff Sgt. Frank Wuterich confirmed his name in a loud, clear voice Thursday as a military hearing began to decide if he should face trial for murder in an attack that left 24 Iraqis dead.

Wuterich faces unpremeditated murder charges in 18 of the deaths in Haditha, making his case the biggest to emerge against any member of the U.S. military to have served in Iraq.

Among those killed in the town on Nov. 19, 2005, were women and children who were scrambling for cover around a bed.

The killings occurred after a military convoy was hit by a roadside bomb that fatally wounded a Marine driver. Wuterich and another Marine shot a group of five men by a car at the scene. The squad leader then directed his men to clear several houses in hopes of killing whoever had set off the bomb. It was Wuterich's first combat engagement.

In determining whether the case should go to trial, the hearing officer, Lt. Col. Paul Ware, must decide if Wuterich strayed from military rules of engagement.

"These Marines were doing exactly as they were trained to do," Wuterich's defense attorney, Lt. Col. Colby Vokey, said earlier this week. "They were responding to an attack and a threat."

Wuterich, 27, of Meriden, Conn., was among four Marines charged with murder and four officers charged with dereliction of duty for failing to investigate the deaths. Prosecutors have dropped charges against two of the enlisted Marines and one officer.

Wuterich told investigators in February 2006 that he believed he was taking small-arms fire from a house near the explosion so he told a four-man team to treat the building and its occupants as hostile, meaning they did not need to identify the occupants as insurgents before opening fire.

"I told them to shoot first, ask questions later," he told investigators.

Wuterich is also charged with making a false official statement and telling another Marine to do the same. He faces a possible life sentence and dishonorable discharge if convicted at court-martial.

Ware already has presided over two separate hearings in the case, when he listened to evidence against two of Wuterich's lance corporals — Stephen Tatum and Justin Sharratt — who were charged with murder. In both cases, Ware found prosecutors could not prove the Marines operated outside combat rules, and he recommended the charges be dismissed.

The general overseeing the case dismissed charges against Sharratt but has yet to rule in Tatum's case.

Tom Umberg, a former Army prosecutor, said Ware's assessment that Tatum and Sharratt did not deliberately violate combat rules could help Wuterich because he was involved in some of the same actions.

But, Umberg said, military officials often look with greater scrutiny at the actions of higher-ranking troops.

"The person in charge always bears the most significant responsibility," Umberg said.

A former squad mate was to testify against Wuterich. Sgt. Sanick Dela Cruz was initially charged with murder, but prosecutors dropped the charges and gave him immunity to testify against Wuterich.

According to testimony in a previous hearing, Dela Cruz claims Wuterich shot the men by the car while they had their hands in the air.

"They were just standing, looking around, had hands up," Dela Cruz said at a hearing in May. "Then I saw one of them drop in the middle. I didn't know what was going on, sir. Looked to my left, saw Staff Sgt. Wuterich shooting."

Neal Puckett, one of Wuterich's nonmilitary attorneys, said he was not concerned about Dela Cruz's testimony and was confident that forensic evidence would contradict his version of events.

"It's a Dela Cruz/Wuterich credibility contest," said Thad Coakley, a major in the Marine reserves and a former Camp Pendleton prosecutor.