The most harmful thing prohibition did was normalize flouting the law, I'd argue it also introduced in popular American culture the concept that an individual could judge the law and decide whether it was just or not.
It seems that this is a fundamental principle in US culture. The nation was born of a revolution. It was literally a triumph of humans and reason over entrenched authority and written law. (Obviously, these people were flawed. They were not infallible moral authorities. This is for anyone who wants to read me as a white-washer.)
Specifically in the legal realm, jury nullification has a long history in British common law. This carried over into pre-revolution American law. It has also carried over to modern law.
https://en.wikipedia.org/wiki/Jury_nullification
https://en.wikipedia.org/wiki/Jury_nullification_in_the_Unit...
Systems always fail. Handle the failures with something better than SIGABRT.