In recent years, Arizona and California overwhelmingly passed ballot initiatives that were expected to divert minor, nonviolent drug offenders from incarceration-jail and prison-to treatment. With respect to the prison population, it was unknown whether low-level drug offenders had a violent or lengthy criminal history that made prosecutors reluctant to drop the low-level drug charge, whether the quantity or type of drug involved influenced the prosecution pattern, and whether there were differences across racial groups in the prosecution of low-level drug offenders. This study was designed to fill those knowledge gaps. The evidence from the period before the implementation of the initiatives supports prosecutors' hypotheses that offenders sent to prison on low-level drug charges generally had more severe criminal histories, were involved with harder drugs, or were caught with substantial quantities. The report's findings also show that marijuana offenders are not first- or second-time offenders and are not treated more "harshly" or more "leniently" than other drug offenders. The authors generally found no differences in treatment of racial/ethnic groups, though in some cases small sample sizes made it difficult to reach definitive conclusions. Plea-bargaining for prison-bound low-level drug offenders appears to be used in a manner consistent with prosecutorial practices aimed at incarcerating drug offenders who are perceived to present a greater threat to the community.