Analyses indicate that neither relevant legal variables (e.g., offense severity and prior record) nor juvenile sociodemographic characteristics inform the detention decision, suggesting the decisionmaking process is idiosyncratic and based on considerations not relevant to the approved purposes of detention. There was no evidence that pretrial detention affected the severity of judicial dispositions. However, those who were detained were more likely to be handled through formal adjudication than informally. As informally handled cases tend to receive more lenient sanctions, this suggests that pretrial detention disadvantages those detained. This effect, however, is not uniform. Juveniles who are male, white, and older were more disadvantaged by detention than were those who were female, nonwhite, and younger. Finally, this effect of detention is small in comparison to the effects of such factors as prior record, offense severity, and race. 49 notes.