In the last 30 years, boys have become less likely to commit crimes, but more likely to be placed in a correctional facility, according to a new study published in the journal Youth Violence and Juvenile Justice. And while boys in all racial groups committed about the same number of crimes, African America and Hispanic boys are more likely to spend time in a facility.

The alarming disparities are the result of the school-to-prison pipeline, where strict discipline measures such as suspensions, expulsions, and classroom arrests from law enforcement presence in the schools feeds students directly into the criminal justice system. The pipeline begins in preschool and the infractions are usually minor such as tardiness or insubordination. An attorney who represents children recalls a young client who was arrested for throwing a pencil.

President Obama’s Administration has recommended that schools end tough “zero tolerance” discipline policies to reverse the trends, illustrated in this must-see chart from Washington Posts’ Wonkblog:

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