If you could count on the police having half a brain and using it, you would be fine. I know in Texas back in the 1950's and 1960's the police would use discretion and would not dream of punishing you even if it was a technical violation of the law. They would realize the law was put in place to prevent unnecessary or random firing of a gun. They would use their common sense and just verbally warn you not to do it again.
Today everything is dependent on political correctness, and so many police think the ‘LAW IS THE LAW” and do not use their common sense or discretion. So I would advise anywhere today if it is against the law, don’t do it, especially in Maryland. If you are in Baltimore I would say it would be even more likely that you would go to jail for such an action.