Defendants whose racial status was recorded as black or Hispanic were categorized as minority defendants. All other defendants were categorized as white. Disparities were estimated in the 10 most populous counties and in a unit composed of the 52 least populous counties as well as for defendants with and without prior arrest records. Results showed that minorities were incarcerated more often than whites, with disparities varying by county. However, removing disparities in post-arrest processing would not significantly reduce the concentration of minorities in jails and prisons. The disparities were attributable to variables that were related to both minority status and case processing decisions and not to prejudice by judges, prosecutors, and defense attorneys. Footnotes, tables, methodological discussion, and 20 references