Using a database obtained from the Clerk of Circuit Court of Cook County, The Chicago Reporter analyzed all misdemeanor cases that were dismissed between 2006 and 2012. The data included defendants’ race, ZIP code, the charges filed against them, and the dates cases were opened and closed. The dismissal rate was based on the number of all misdemeanor cases opened between 2006 and 2012, according to the Administrative Office of the Illinois Courts. A second database from the clerk’s office was used to figure out the number of cases, for each crime category, that resulted in convictions between 2006 and 2011. To determine whether a police officer was the most likely witness in any given dismissed cases, the Reporter analyzed the type of crime. Charges involving drugs, prostitution and disorderly conduct, for example, were among those categorized as having police as a likely witness. Assault, theft and property damage were among the charges categorized as having a victim as witness. The Reporter categorized charges like trespass and fraud as a “toss-up.” The estimated cost of dismissed cases was calculated by tallying the expenses for arrest, booking, pre-trial assessment and, in some cases, detention associated with opening a misdemeanor case. According to the Appleseed Fund for Justice and the Chicago Council of Lawyers, the costs are $202.96, $299.15 and $29.04, respectively. A stay at the Cook County Jail costs $143 each day.