I wonder outside of TV, how many crimes are prevented by tracing guns? At some point we have to trust our fellow man to use good judgement. Every day I drive p

I wonder outside of TV, how many crimes are prevented by tracing guns? At some point we have to trust our fellow man to use good judgement. Every day I drive past cars going the other way at a combined speed > 60mph and the only thing protecting me is a couple of lines painted on the road.