Intoxication
There is no power on earth who can bar a sane adult from administering an intoxicating substance on himself, so long as it does not cause direct harm to other life, or render himself an unproductive social animal.
The sale, possession or use of recreational intoxication substances is a crime in most jurisdictions. The problem with de-criminalising these acts is that most users fail to regulate themselves, abuse these substances, get addicted and render themselves useless and a liability to society. Some of them cause direct harm to others as well. Tracking substance use to enforce responsible use would infringe many fundamental rights of an individual, thus making prohibition of most intoxicating substances the only appealing alternate option against the epidemic of substance abuse. Those who enjoy these substances responsibly pay for the mistakes of others.