Three customers restrained the 16-year-old at a West Allis convenience store in Dec., 2012, after he was spotted loading alcohol into his backpack.
Earlier this week, the Milwaukee DA announced he would not file charges against the three male customers, stating he could not prove they intended to kill Stingley or even knew their actions could cause his death. He died about two weeks after the event, when his family removed him from life-support.
According to the Medical Examiner's report, the cause of the teen's death was a lack of oxygen to the brain, caused by the physical struggle and restraint.
Stingley's family is pursuing a federal civil rights investigation into the case. The Nathan Hale High School student was black; the three customers, white.