The Impact of a Risk Assessment Instrument on Juvenile Detention Decision-making: A Check on "Perceptual Shorthand" and "Going Rates"?

This study assesses the impact of a juvenile detention risk assessment instrument (RAI) on decision-making in five New Jersey counties. It uses a pretest-posttest design, drawing on a sample of decisions matched across time periods using propensity scores (N=1,432). It suggests that the RAI, supported by other reforms, lowers overall rates of detention. Though evidence is not strong, findings suggest the RAI may have reduced reliance on "perceptual shorthand" variables reflected in the juvenile's age and the time of day of the decision. There is stronger evidence that the RAI increased reliance on the specific factors contained within its risk score. There is also evidence that RAI reduced disparities in detention rates across counties, perhaps by diminishing the importance of "going rates" for detention, rooted in local courtroom workgroups.