Your car, your problem. Either get someone to fess up, or take responsibility yourself and stop loaning it out.
There really is no difference between "who drove through a red light" and "who scratched the bumper while parking" here - how do you currently solve the latter one?
There really is no difference between "who drove through a red light" and "who scratched the bumper while parking" here - how do you currently solve the latter one?