Your entire hypothesis rests on the fact that you believe that no law should be allowed that prevents an event from occurring. Thus a Boeing jet where faked screws are used should never lead to a prosecution if those fake screws hold fast. Thus if two independent operators sell and use these fake screws, only the ones who cause a crash should be prosecuted, even though the other group independently put the entire plane full of people at risk.

I hope that's a more "reasonable" example.