Is there a fallacy that fits the logical error of saying that if something is a law, then it’s right? Not a natural law or scientific law, but one that was written by lawyers and voted on. It could fall under an argument from authority, except if it’s a law, then the people who actually are the authority, made the law. Of course it’s just a law, and laws made by people are fallible, so it’s provisionally right, but not right in the universal sense. Any law is just an attempt to formalize what everybody thinks is right at the time.
It’s also somewhat related to the is-ought problem. Just because there is a law about how to use marijuana, that doesn’t mean there ought to be one. This is different than the problem of pointing to how nature works because monkeys have acted like they do for thousands of years but marijuana laws have been in flux for 100 years.