House Minority Leader Nancy Pelosi delivers remarks beside House Speaker John Boehner at the signing ceremony of the Justice for Victims of Trafficking Act on Capitol Hill in May. (Michael Reynolds/European Pressphoto Agency)

OVER-INCARCERATION has received much attention lately, but an important population has mostly been overlooked: girls. They were the focus of a recent report on sexual abuse that points to gaping holes in the criminal justice and child welfare systems.

According to data collected by the Human Rights Project for Girls, the Georgetown Law Center on Poverty and Inequality and the Ms. Foundation for Women, in some states more than 80 percent of incarcerated girls have been sexually abused, either behind bars or before their confinement. Girls of color and lesbian, bisexual or transgender girls suffer at even higher rates. What’s especially maddening is that most aren’t behind bars for violent felonies but for offenses arising from their victimization — such as running away from home or engaging in prostitution.

The Justice for Victims of Trafficking Act of 2015, which became law in May, held those who purchase sex from minors accountable for their crimes and directed criminal fines toward a fund for victimized girls. That should help. But, though another federal law prohibits incarceration of children on prostitution charges, most states haven’t followed suit. As a result, many police departments and judges continue to arrest and punish the wrong people: Girls who are victims of sexual trafficking end up in handcuffs, while the criminals selling and buying them walk free.

Congress is set to reauthorize the Juvenile Justice and Delinquency Prevention Act in the coming months. It should use the opportunity to strengthen protections for minors. Congress should bear down on states to change their rules and practices, and states should make those changes.

That success, though, would lead to another challenge: Where do these girls have to go? It will take hard work and resources to keep girls away from the homes (often foster homes) where they were abused and off the streets where they were sold.

There are ways. Florida’s Practical Academic Cultural Education (PACE) program, for example, provides at-risk girls with specialized academic attention, trauma and career counseling, and at-home check-ins. Nine out of 10 PACE students have ended up back in school, at college or employed, and at $16,000 per girl per year, PACE has a lower price tag than the average rate of $42,000 to incarcerate. Florida’s success suggests that, by diverting funds from juvenile detention to programs such as PACE, governments can save money and lives. This new report gives Congress and states another push to start doing so.