The current study advances past research by studying the impact of juvenile justice decision making with a geographically and ethnically diverse sample (N = 1,216) of adolescent boys (ages 13–17 years) for the 5 years following their first arrest. Importantly, all youth in the study were arrested for an eligible offense of moderate severity (e.g., assault, theft) to evaluate whether the initial decision to formally (i.e., sentenced before a judge) or informally (i.e., diverted to community service) process the youth led to differences in outcomes. The current study also advanced past research by using a statistical approach that controlled for a host of potential preexisting vulnerabilities that could influence both the processing decision and the youth's outcomes. Our findings indicated that youth who were formally processed during adolescence were more likely to be re-arrested, more likely to be incarcerated, engaged in more violence, reported a greater affiliation with delinquent peers, reported lower school enrollment, were less likely to graduate high school within 5 years, reported less ability to suppress aggression, and had lower perceptions of opportunities than informally processed youth. Importantly, these findings were not moderated by the age of the youth at his first arrest or his race and ethnicity. These results have important implications for juvenile justice policy by indicating that formally processing youth not only is costly, but it can reduce public safety and reduce the adolescent's later potential contributions to society.