CAMP PENDLETON - Charges have been dropped against a Marine captain accused of criminal dereliction of duty for failing to investigate the deaths of two dozen Iraqi civilians in the city of Haditha in November 2005, military officials announced Tuesday.

The move leaves two of four officers and two of four enlisted men originally charged in the case still facing the possibility of courts-martial.

Capt. Lucas McConnell was charged with two counts of dereliction after Marine prosecutors said he failed to ensure the deaths were accurately reported and that the incident was immediately investigated.

In dismissing the charges, Lt. Gen. James Mattis ordered McConnell to cooperate with prosecutors and granted him immunity, meaning the 32-year-old officer's testimony against other Marines cannot later be used against him.

McConnell's attorney, Kevin McDermott, said his client didn't do anything wrong, that he never sought a deal and never asked for the immunity. He is not willing to cooperate with prosecutors, McDermott said.

"The government's case is falling apart around them and they need to make this look like an officer will be cooperating against the balance of the defendants," McDermott said. "Far from true; he will not."

The Marine Corps said in a statement issued Tuesday afternoon that Mattis decided unspecified "administrative measures are the appropriate response for any errors or omissions allegedly committed by McConnell."

Those measures could include a "letter of caution" or an appearance before a general for what is known as nonjudicial punishment.

McConnell was commanding officer of the company that included the squad involved in the incident, but was not present when the Iraqis were killed.

The Haditha killings caused an international uproar when they became public in March of last year. A subsequent investigation into how the civilians died led to dereliction of duty and related charges against four officers and murder charges against four enlisted men.

The shootings followed a roadside bombing that killed a lance corporal and injured two other Marines.

Hearings at Camp Pendleton this year led to the dismissal of charges against one of the officers, Capt. Randy Stone, and one of the enlisted men, Lance Cpl. Justin Sharratt.

Lt. Col. Paul Ware, the officer who presided over Sharratt's hearing, also oversaw the hearing for a second enlisted man, Lance Cpl. Stephen Tatum. Ware has recommended that murder charges against Tatum also be dropped. A decision on that recommendation is pending.

In his reports, Ware said there was convincing evidence that the lance corporals believed they were confronting armed insurgents.

Ware also presided over a hearing for Staff Sgt. Frank Wuterich, the Kilo Company squad leader from Camp Pendleton's 3rd Battalion, 1st Marine Regiment. During that hearing, Wuterich said he did not believe he or his squad did anything wrong in Haditha, but that he mourned the civilian deaths.

Wuterich, who faces 17 counts of murder, was leading his squad on a resupply mission in Haditha on the morning of Nov. 19, 2005, when the bomb destroyed one of four Humvees, killing Lance Cpl. Miguel Terrazas and injuring the two other Marines.

Moments later, five men who emerged from a car that drove up were killed by Wuterich and another Marine.

Nineteen other Iraqis would die in the next few hours as Wuterich and his Marines stormed four homes after being ordered to take that action by Lt. William Kallop, who wasn't charged in the case.

The man who commanded the battalion at Haditha, Lt. Col. Jeffrey Chessani, is awaiting word on whether he will face trial. The investigating officer who presided over his hearing has recommended he face court-martial.

Brian Rooney, one of Chessani's attorneys, said the lieutenant colonel's defense team was happy with the decision in the McConnell case.

"Nothing he (McConnell) can say will hurt us," Rooney said. "He was the one who talked to Lt. Kallop and the Marines involved, and it was based upon his report that Col. Chessani accepted what had happened."

The fourth officer charged in the case, 1st Lt. Andrew Grayson, is scheduled to have his hearing sometime next month.

The fourth enlisted man charged with murder, Sgt. Sanick Dela Cruz, had five murder counts against him dismissed in exchange for his testimony.

Earlier this month, the secretary of the Navy issued letters of censure to three Marine officers who weren't charged with wrongdoing at Haditha but were in the chain of command. The letters that went to Maj. Gen. Richard Huck and Cols. Stephen Davis and Robert Sokolosk said they had failed to carry out their duties.

- Contact staff writer Mark Walker at (760) 740-3529 or mlwalker@nctimes.com.