Legal Question in Constitutional Law in California

Re: Alcohol Prohibition vs. Drug Laws

You mistakenly presume that something which was done via a Constitutional amendment could not have been done any other way.

The constitution neither permitted nor banned alcohol before the 18th Amendment was added in 1919. The ban could have been accomplished by federal statute (or by 50 state statutes), but its supporters got it into the Constitution instead.

I don't know the amendment's history, but my educated guess is that supporters realized that opponents would try to overturn the ban and knew that putting it into the Constitution would make overturning it more difficult. Opponents managed to do so anyway, by adding the 21st amendment in 1933 to repeal prohibition.

An amendment was the only way to repeal prohibition because, at that time, the Constitution expressly forbade the sale of alcohol. The situation was thus quite different from the one in which prohibitionists operated before 1919, when a Constitutional amemdment was just one of multiple ways they could have accomplished their goal.

Banning controlled substances today is like banning alcohol would have been before 1919. It can be done via an amendment, but can also be accomplished via federal statutes like the one you ask about. Such statutes might be unconstitutional if they are written in ways that conflict with existing constitutional provisions, but careful drafting should prevent such conflicts. There is nothing inherently unconstitutional about statutes which ban or regulate drugs.

Re: Alcohol Prohibition vs. Drug Laws

Just a minor correction to my prior answer:

I said earlier that prohibition could have been accomplished "by 50 state statutes" instead of by Constitutional amendment or federal statute, but when the 18th Amendment was ratified in 1919 there were only 48 states.

More importantly, there is a practical difference between a law enacted by the federal government and one enacted by each state and territory. In the former case the federal government would enforce the law, but in the latter case enforcement would be left up to the individual states and territories. The same conduct would be made illegal either way, but how the law would be enforced could vary quite a bit from one state to another. For instance, even if similar offenses would result in similar sentences in two different states, the offender might be eligible for parole sooner in one state than in the other. Additionally, it might be easier to get away with breaking the law in one state than in another due to different law enforcement priorities or other factors that vary from one state to another.