Never confuse legislation with law. A law is something timeless, which has always existed, and which will always exist regardless of whatever legislation exists. For example, the law is that trespassing on railroad tracks when a train is present carries the death penalty and trespassing when a train is not present has no penalty at all. Wise legislation puts a penalty on trespassing on railroad tracks at all times, with the goal of averaging out the penalty.
The law is that most people will be dissatisfied from time to time with their mental state, and they will seek to change it using psychoactive substances. That's the law. No legislation can change that. Foolish legislation tries. You can tell that it's foolish because it doesn't change the law at all.
The law is that people cannot accurately estimate the magnitude of the effects of alcohol on their brain. Legislation recognizes that law by establishing a limit on the level of alcohol in the blood as evidence of impairment.
There are many more examples of laws, and legislation which complements or opposes the law. Go find your own.