Former Sgt. Frank Wuterich ended his service Friday, said Marine Corps spokesman Lt. Col. Joseph Kloppel.
Wuterich's attorney, Neal Puckett, said in an email to The Associated Press on Tuesday that the Corps gave him a general discharge under honorable conditions -- one step below an honorable discharge.
Wuterich had his rank reduced to private as part of a plea deal that abruptly ended his manslaughter court martial last month at Camp Pendleton and spared him imprisonment.
The 31-year-old father of two pleaded guilty to negligent dereliction of duty as the leader of the squad that killed 24 Iraqis after a roadside bomb exploded in the town, killing a fellow Marine and wounding two other Marines.
After reaching the deal, Wuterich apologized for the loss of life but said his squad did not behave badly or dishonorably. He also defended his order to raid homes in Haditha because he believed his squad was under attack. He acknowledged he instructed his men to "shoot first, ask questions later."
His case ended a six-year prosecution that failed to win any manslaughter convictions in one of the worst attacks on Iraqi civilians by U.S. troops during nine years of war. Eight Marines were initially charged in the case. One was acquitted and six others had their cases dropped.
The outcome of the case sparked outrage in Iraq and the government there has said it will take legal action to ensure justice for the families of the victims. But officials did not give specifics and it was unclear what action could be taken.
Wuterich, who is originally from Meriden, Conn., was forced to stay in the military until his case was resolved. Puckett said he is looking for a job in information technology. He lives with his two daughters in Southern California.
Wuterich could not be reached for comment by The Associated Press. Puckett said his client was not making public statements on his leaving the service.