Army Sergeant 1st Class Tracy Perkins was cleared on Friday of a charge of involuntary manslaughter, but found guilty on charges of assault and obstruction of justice. He was also cleared on a charge of making false statements.
Sentencing of Perkins, 33, a 14-year army veteran, will begin on Saturday by the same jury panel. He faces a maximum of 11.5 years in prison on his conviction for assault and obstruction of justice.
The military panel had deliberated for more than 16 hours before delivering its verdict late on Friday night.
Perkins was accused of killing Zaidun Hassun, 19, by having soldiers force him and a cousin off a ledge above the Tigris river in Samarra, Iraq in January 2004.
The cousin, Marwan Fadil, testified on Wednesday that the soldiers tossed the two at gunpoint into the water after they begged for mercy and then laughed as Hassun drowned.
Defence lawyer Captain Joshua Norris said the panel should not convict Perkins because there was "no body, no evidence, no death". Soldiers testified both men made it safely to shore and that the death may have been faked.
The drowning incident almost went untold until a popular online blog - http://healingiraq.blogspot.com - posted a public appeal from Hassun's mother calling for an investigation into her son's death.
She claimed the two cousins had been hauling toilet spare parts from Baghdad to Samarra when their truck broke down on 3 January.
A number of US soldiers were
put on trial for abusing Iraqis
After repairing it, they were stopped at a US checkpoint at 15 minutes before the beginning of the 11pm nightly curfew. The two Iraqis were allowed to pass but were then followed by a "mechanised vehicle".
They were stopped, forced out of their truck, handcuffed and taken to a bridge overlooking the Tharthar Dam where they were then allegedly forced to jump into the Tigris river.
Hassun's mother wrote an open letter to US President George Bush and British Prime Minister Tony Blair pleading for an investigation into her son's death.
An investigation was opened by US occupation forces on 8 January.