Pvt. Danny Chen, 19, was found dead in a guard tower last year, apparently from a self-inflicted gunshot wound. Holcomb and seven other soldiers faced charges relating to his death.
Holcomb was found guilty Monday by a court martial panel of maltreatment and assault. Besides the reduction in rank to E-4 and the 30-day sentence, he will also have to forfeit slightly more than $1,000 of pay, according to a statement from the press office at Fort Bragg, North Carolina.
He was cleared on the more serious charge of negligent homicide.
When it announced the charges, the Army did not specify what acts were alleged to have been committed by the soldiers, but family members said Chen had complained in letters of harassment by fellow soldiers before his death.
An Army official said the soldiers were essentially charged with hazing and abusing Chen in the weeks and days before he killed himself.
The Chen family told The New York Times in October that officials said Chen had suffered physical abuse and ethnic slurs by superiors, including an incident in which he was dragged out of bed and across the floor for failing to turn off a water heater after showering.
At a vigil for Chen last year, his brother, Banny Chen, read from a letter the soldier had sent to his family.
“They ask if I’m from China a few times a day. They also called out my name, ‘Chen,’ in a goat-like voice sometimes for no reason. No idea how it started, but it’s just best to ignore it.”
The seven other soldiers facing charges are expected to be tried in the coming months.
