Legal regulation can be used in four general ways to influence the incidence, prevalence, patterns, and circumstances of consumption of potentially harmful substances—including ALCOHOL, TOBACCO, and other DRUGS. The most direct mode of legal intervention is to establish the conditions under which a potentially harmful substance is available. In doing so, the law can employ either

1. a "prohibitory" scheme that prohibits the production or distribution of the substance for nonmedical or self-defined uses, or
2. a "regulatory" regime, which permits the substance to be lawfully available for nonmedical or self-defined uses but that may regulate the product, its price, and the conditions under which it is accessible.

A completely successful prohibition would prevent any nonmedical consumption of the proscribed substance; however, the more likely consequence of a prohibitory scheme is that an illicit distribution system will arise to...