Formal System Processing of Juveniles: Effects on Delinquency
Authors: Petrosino Anthony , Turpin‐Petrosino Carolyn , Guckenburg Sarah 
Published: June 2013

The objective of this Campbell systematic review is to answer the question: Does juvenile system processing reduce subsequent delinquency? The comprehensive search yielded 29 eligible controlled trials including 7,304 juveniles reported over a 35‐year period.Juvenile system processing, at least given the experimental evidence presented in this report, does not appear to have a crime control effect. In fact, almost all of the results are negative in direction, as measured by prevalence, incidence, severity, and self‐report outcomes. The results are not uniform across every study; one important moderating variable is the type of control group. Studies that compared system processing to a diversion program reported much larger negative effect sizes than those that compared it to “doing nothing”.Based on the evidence presented in this report, juvenile system processing appears to not have a crime control effect, and across all measures appears to increase delinquency. Given the additional financial costs associated with system processing (especially when compared to doing nothing) and the lack of evidence for any public safety benefit, jurisdictions should review their policies regarding the handling of juveniles.Executive Summary/AbstractBACKGROUNDJustice practitioners have tremendous discretion on how to handle juvenile offenders. Police officers, district attorneys, juvenile court intake officers, juvenile and family court judges, and other officials can decide whether the juvenile should be “officially processed” by the juvenile justice system, diverted from the system to a program, counseling or some other services, or to do nothing at all (release the juvenile altogether). An important policy question is which strategy leads to the best outcomes for juveniles. This is an important question in the United States, but many other nations are concerned with the decision to formally process or divert juvenile offenders. There have been a number of randomized experiments in the juvenile courts that have examined the impact of juvenile system processing that should be gathered together in a systematic fashion to provide rigorous evidence about the impact of this decision on subsequent offending by juveniles.OBJECTIVESOur objective is to answer the question: Does juvenile system processing reduce subsequent delinquency?CRITERIA FOR INCLUSION OF STUDIESTo be eligible, studies had to: (1) use random or quasi‐random (e.g., alternation) assignment to allocate participants to conditions; (2) include only juvenile delinquents ages 17 and younger who have not yet been “officially adjudicated” for their current offense; (3) assign such participants to juvenile system processing – or to an alternative non‐system condition; (4) include at least one quantifiable outcome measure of criminal behavior; and (5) be reported through July 2008 (without regard to language).SEARCH STRATEGYFifteen experiments that met the eligibility criteria were identified from prior reviews conducted by the authors. To augment these 15 trials, we relied on electronic searches of 44 bibliographic databases, examined the citations in over 50 existing meta‐analyses and reviews to identify additional randomized studies, and contacted researchers outside the U.S. to identify non‐US. studies. These additional search strategies yielded 40 studies that required inspection of full‐text documents, resulting in an additional 14 experiments that met the eligibility criteria. Taken together with the existing 15 trials from our preceding reviews, these additional searches resulted in a final sample of 29 controlled trials.DATA COLLECTION AND ANALYSISA preliminary instrument was designed to extract data on substantive and methodological characteristics from each of the 29 trials. Standardized mean differences (Cohen's d) effect sizes were computed for the first, longest and strongest effects reported in each study for juvenile system processing, using Comprehensive Meta‐Analysis (version 2)1. Given the heterogeneity of the sample, analyses of effect sizes were reported assuming random effects models. Main effects were analyzed for each type of crime measure reported: prevalence, incidence, severity and self‐report. Five moderating analyses were also conducted.MAIN RESULTSThe studies included 7,304 juveniles across 29 experiments reported over a 35‐year period. Juvenile system processing, at least given the experimental evidence presented in this report, does not appear to have a crime control effect. In fact, almost all of the results are negative in direction, as measured by prevalence, incidence, severity, and self‐report outcomes. The results are not uniform across every study; one important moderating variable is the type of control group. Studies that compared system processing to a diversion program reported much larger negative effect sizes than those that compared it to “doing nothing.AUTHORS' CONCLUSIONSBased on the evidence presented in this report, juvenile system processing appears to not have a crime control effect, and across all measures appears to increase delinquency. This was true across measures of prevalence, incidence, severity, and self‐report. Given the additional financial costs associated with system processing (especially when compared to doing nothing) and the lack of evidence for any public safety benefit, jurisdictions should review their policies regarding the handling of juveniles.