CAMP PENDLETON -- The highest-ranking officer to be charged in connection with the deaths of 24 Iraqis in Haditha appropriately reported the killings and was not criminally derelict in failing to call for an investigation, the officer's attorney argued Monday as his 10-day hearing ended.

"This case does not warrant criminal charges," said Robert Muise, a civilian attorney representing Lt. Col. Jeffrey Chessani, in court. "The actions he took were in good faith."

Chessani is charged with dereliction of duty for what military prosecutors maintain was his failure to fully investigate the deaths, which followed a deadly roadside bomb explosion on a chaotic day of battle on Nov. 19, 2005.

Chessani was commander of Camp Pendleton's 3rd Battalion, 1st Marine Regiment at the time. His attorneys contend Chessani reported everything he knew about the incident immediately after it happened.

Aside from Chessani, three other officers face dereliction charges for not ordering a probe of the deaths. Three enlisted men from the battalion face murder charges.

Military prosecutor Lt. Col. Sean Sullivan argued that a deeper probe of the deaths -- which included the killings of two women and five children in homes near the bomb site -- should have been an obvious step.

"I think it was a conscious, willful decision not to investigate," Sullivan said. "That event screamed out for investigation."

Both sides made their closing arguments Monday at a hearing to determine if Chessani should face a military trial. Hearing officer Col. Christopher Conlin will make his recommendation to Lt. Gen. James Mattis about whether the officer should be sent to trial.

Chessani could face more than two years behind bars and dismissal from the service if he is tried and convicted.

Nineteen Iraqis died inside homes that Marines, who were under gunfire right after the explosion, stormed in search of insurgents. Five other civilians were killed after emerging from a car that drove up shortly after the explosion, which killed a lance corporal and injured two other Marines.

Charges arising from the Haditha deaths make up one of the largest criminal cases in the more than four years since the U.S. invasion of Iraq.

Prosecutors have argued that Chessani's faith in the Marines under his command led him to reject the idea that the fatalities were anything but casualties of war.

"You want to believe in your Marines," Sullivan said, "but that doesn't negate your duty to investigate."

Sullivan also pointed to a letter that the mayor and members of Haditha's city council supplied in English to Chessani in the days after the shootings, asking for an investigation.

"The one man that should have been asking the hard questions was the battalion commander," Sullivan said.

Muise, Chessani's attorney, said the letter from Haditha leaders was a propaganda tool, and that some of them had ties to the insurgency.

He also argued that many high ranking military officers saw the dead as collateral damage in an attempt to ferret out insurgents who may have been hiding in the homes, and that the incident raised no red flags for Chessani's superior officers. None of them called for an investigation either, Muise said.

The case surrounds one of two incidents in which Camp Pendleton Marines are accused of killing at least one civilian. Several men from another unit are charged with killing a civilian in the village of Hamdania in 2006.

In the Hamdania case Monday, military prosecutors dropped assault charges they had levied against a Camp Pendleton sergeant who is also charged with kidnapping and killing a retired Iraqi policeman.

Murder and other charges still remain in place for that Marine, Sgt. Lawrence Hutchins, who prosecutors call the alleged architect of the Hamdania slaying plot.

In the Haditha case, a media report in March 2006 on the deaths eventually spurred a criminal probe and a formal look at how the report of the civilian deaths was handled. In the wake of the investigations, Chessani was stripped of his command when his unit returned from Iraq in April 2006 .

Chessani's attorney said it was "crucial to put his decisions in context" of the situation and the number of battles and firefights that day.

"It's very easy for all of us to sit here today and second guess his decisions," Muise said.

Muise argued that stripping Chessani of his command -- which essentially ended his once-bright military career -- was a severe enough punishment.

After court, Muise said he has been told that, prior to the Haditha incident, Chessani was on track to become a general someday, and had received a number of glowing reports about his work. Chessani is eligible for full retirement in November, when he reaches 20 years of service.

Chessani's is the second of the four officers accused of dereliction to have finished up a hearing to determine if the case should go to trial. Last week, a hearing officer recommended that the government dismiss criminal charges against Capt. Randy W. Stone, and handle his case with administrative punishment.