prevalence—the number and percentage of people in various demographic groups that have recently or have ever used drugs—than to a careful description of the quantity and frequency and consequences of use, or to the causal relationships among these variables (see MacCoun, 1998; Reuter and Caulkins, 1995). The emphasis on prevalence is explicit in the National Drug Control Strategy (NDCS) reports published by the White House over the past decade, which provide an annual list of specific national goals for drug policy. For many years, the list consisted entirely or almost exclusively of goals pertaining to reductions in the prevalence of drug use. The 1998 document, Performance Measures of Effectiveness, was an important departure in this respect, offering a lengthy and detailed list of goals pertaining to reductions in various indices of the quantity of drug consumption and its health and behavioral consequences.
The long-time emphasis on prevalence is understandable. Logically, most (but not all) of the risks of drug use are borne only by those who decide to use drugs; if there were no drug users, there would be no drug-related harms. The threshold separating the nonuser and the user is viewed as a kind of irrevocable Rubicon in the formal perspective of criminal law, as well as the informal perspective of concerned parents, spouses, and teachers. Tracking trends in prevalence is and should be an essential metric for drug policy analysis, but it is a fairly limited one, based on a crude dichotomy between those who use and those who do not use drugs.
In this section, we argue that that there are compelling reasons to expand and improve the monitoring and analysis of the consequences of drug consumption. Such improvements would lay the foundation for analyzing the complex relationship between drug use patterns and their consequences. We then raise some largely unexplored conceptual and analytic issues involving the complex relationship between drug use patterns and their consequences. We end with a discussion of the effects of laws and their enforcement on the consequences of drug use.
Box 2.2 provides a list of major categories of harmful consequences associated with drug use in contemporary American society; the list has several notable features. First, the categories of consequences are quite heterogeneous—medical, psychological, sociological, and economic. Second, the consequences vary with respect to their primary bearers—some are mostly borne by users themselves, others by their intimates and neighbors, others by society. Third, some flow primarily from the psychopharmacological properties of the drugs and their effects on user behaviors, while others are at least partly attributable to the acquisition and use of