A number of pre-trial release studies which have been conducted during the past several years show that various measures of criminal activity while on release vary from 7.9 percent (reindictment for those indicted on felony charges) to 70 percent (re-arrest of those originally arrested on a robbery charge). Little actual sentence data were available for or presented in these studies, and no personal data on the defendants or facts about the crimes themselves were shown. This document describes a pilot study of a thorough analysis of criminal cases, including both felonies and misdemeanors, in a four week sample of cases in the District of Columbia during the first half of 1968. The method of data collection is described, together with attendant problems. Summary data for 712 defendants in a sample of 4 weeks taken from the first half of 1968 are presented. Comparisons are made to show the re-arrest rates for defendants initially charged with particular classes of crime. Personal characteristics are examined to determine if any are significant predictors of recidivism. A recidivism index is formulated to give the rate of re-arrest per man-day of exposure. Robbery cases are examined in more detail. (Author).