Webjames crumbley, the father of the teenager who killed four students at a michigan high school in 2021, was found guilty thursday of involuntary manslaughter in a trial that comes a month. Webjennifer and james crumbley, the parents of michigan school shooter ethan crumbley, were sentenced to 10 to 15 years in prison. The crumbleys were found guilty of involuntary manslaughter in.