Sounds to me like Bill Buckley was advocating the application of science rather than pure ideology to our government's handling of the drug situation.
Some cities have laws against consumption of alcoholic beverages on public rights-of-way, regardless of whether the person consuming them acts intoxicated. Whether or not such laws are a good idea, I see nothing inherently wrong with them.
More generally, I see nothing wrong with laws that forbid people from doing certain things in places where they may be observed by others who are not specifically looking for them. There should be different tiers of punishment based upon whether the behavior's visibility was a result of deliberate action, recklessness, negligence, or bad luck. Exposure due to bad luck shouldn't be punished, but may be logged; excessive "bad luck" could point to negligence or worse.