There was an episode of The Good Wife about ghost runs. I liked that show because it was never preachy as you never cared about either party. Often humorous. In the ghost gun episode some guy printed a gun and used it at a firing range. It blew off the face of the guy behind him. Who gets sued? Everybody. The person who posted the plan, the user who modified it, the polymer manufacture, the 3D printer maker, etc.