If our goal is to mitigate whatever factors are most likely to draw young people into contact with the justice system, the interventions we provide should reflect what we know about adolescents and the conditions facing young people in the United States today.

JJIE—Interpreting the Juvenile Incarceration Drop

Even if we observe a number of instances when state reforms are followed by lower incarceration, we have to test whether the causal hypothesis holds up in the absence of reform? If we lined up all the states according to whether they had enacted meaningful reforms in their juvenile justice systems, would their incarceration trends line up in the same way, with high reform states showing more decline and low reform states showing less? Moreover, does the relationship persist over time and under varying circumstances?