Staff Sgt. Edward W. Deptola was accused of the desecration of remains and posing for unofficial photographs with human casualties. He also was accused of failing to properly supervise junior Marines and not reporting the misconduct.
Deptola and another Marine based at Camp LeJeune were charged last year after video surfaced showing four Marines in full combat gear urinating on the bodies of three dead Afghans in July 2011. In the video, one of the Marines looked down at the bodies and quipped, "Have a good day, buddy."
Deptola, a decorated veteran of Iraq and Afghanistan whose age was not released, was sergeant for a scout sniper platoon. He admitted to the military judge that he failed to supervise the Marines under him when the desecration began, even though he had been briefed that such behavior violated Geneva convention rules.
"I was in a position to stop it and I did not ... I should have spoken up on the spot," he said.
When asked by the judge why he did it, Deptola said "I have no excuse, no reason, ma'am ... it was not the correct way to handle a human casualty."
The urination video surfaced amid a string of embarrassing episodes for U.S. forces in Afghanistan. American troops were caught up in controversies over burning Muslim holy books, posing for photos with insurgents' bloodied remains and an alleged massacre of 16 Afghan villagers by a soldier.
The sentencing phase against Deptola continued Wednesday afternoon. While he could face a maximum punishment of a year in prison, forfeiture of pay and demotion to private, the other Marines involved have negotiated lower sentences.
Staff Sgt. Joseph W. Chamblin pleaded guilty to similar charges last month. Under a deal reached before his court-martial, he lost $500 in pay and was reduced in rank to sergeant. Three other Marines were given administrative punishments for their roles.
The Marine Corps said the urination took place during a counterinsurgency operation in the Musa Qala district of Helmand province, located in the south of the country.
After the video garnered international attention on YouTube, senior military officials sternly condemned the behavior of the Marines involved.
The United States now has 66,000 troops in Afghanistan. The U.S. and its NATO allies agreed in November 2010 that they would withdraw all their combat troops by the end of 2014, but they haven't decided on the scope of future missions in the country and the size of any residual force remaining after that.