The case could set a precedent for holding parents criminally responsible for the actions of a child.
Prosecutors accuse the Crumbleys of ignoring signs their son was troubled and could become violent and instead buying him the hand gun he used to kill four students and wound seven other people at Oxford High in 2021.
The prosecution alleges the parents could have stopped the massacre before it began but never mentioned to school officials the teen might have access to a gun.
Defense attorneys counter it was the son who pulled the trigger, not the parents, and that they had no idea he wanted help...or planned a mass shooting.
The parents requested separate trials saying there is evidence that could pit the couple against each other.
