THE CHALLENGES OF MEASURING THE IMPACT OF THE DRUG COURT PHENOMENON

This article argues that evaluation of drug courts will benefit not only from an organizing typology (Goldkamp, 1999a, 2000) that focuses research on the critical structural elements of the drug court model but also from an understanding of how drug courts are thought to deliver their impact. In developing a causal model of drug court impact, the analysis separates assessment of impact into two investigations: whether drug courts “work ” and how they work. Data from the ongoing NIJ-supported evaluation of the Portland and Las Vegas drug courts are analyzed to answer the comparative question of whether there is an impact (and of what sort) and then to move consideration of the internal elements of the drug court (the black box of drug court treatment) through the development of successive theoretical models. The illustrative analyses guided by these models consider the relative contributions of instrumental drug court treatment functions and defendant risk attributes, which contribute importantly to drug court outcomes. The exploratory findings differ by site, but show some support for the importance of treatment, sanctions and appearances before the drug court judge—and their interaction—in lowering the prospects for subsequent rearrest and increasing likelihood of graduation