
Data Needed to Measure DisparityIf you think of the juvenile justice system as a set of individual decisions, we can assess the level of racial disparity introduced at each decision point—if the numerator and denominator used to construct the rates are carefully selected. The general approach in creating the rates to be used is to select a denominator that captures the decisionmaking stage immediately preceding the stage measured by the numerator or, in other words, the stage that feeds the numerator. For example, to a great extent arrests feed juvenile court referrals; if arrests increase, most likely juvenile court referrals will increase. There are certainly other paths to juvenile court beyond arrest (e.g., parents may refer youth or a probation officer may refer a youth back to court on a probation violation); but arrest is the most controlling preceding stage. And for the detention, diversion, and petition decisions, referral to court is the feeder stage, and so on through system processing decision points. In practice, sometimes the data at one stage is not available. For example, we know that the race/ethnicity groups included in national arrest estimates do not match those in the juvenile court data. As a result, the "by race/ethnicity" and "by gender and race/ethnicity" tables use population estimates as the denominator for referral rates. For the "by gender" table, arrests are used as the denominator to create referral rates. For the remaining stages, rates are created as follows:
Using a set of case processing rates (e.g., juvenile court referral rate, detention rate, diversion rate, petition rate, waiver rate, adjudication rate) and the ratio of rates at each decision point allows us to compare demographic subgroups. The ratio between one group's rate for a decision point and another group's rate for the same decision point quantifies how much more, or less, likely an outcome is for members of different subgroups. A ratio of 1.0 indicates parity, i.e., the rates for both groups are equal. For example, if white youth and Black youth were referred to juvenile court at the same rate, the ratio of their referral rates would be 1.0. A ratio greater than 1.0 means that the rate for the racial/ethnic minority group is greater than the rate for white youth; a ratio less than 1.0 means that the rate for the racial/ethnic minority group is less than the rate for white youth. The magnitude of racial and ethnic disparity at any decision point in the juvenile justice system is a combination of the disparities introduced at prior decision points plus that added by the decision point of interest. Studying the ratio of rates for a specific decision point enables us to see the unique contributions made by each stage to the overall disparity in the system. Developed and maintained by the National Center for Juvenile Justice, with funding from the Office of Juvenile Justice and Delinquency Prevention (OJJDP), Office of Justice Programs, U.S. Department of Justice.
