FILE - In this May 17, 2011, file photo, a bus drives past the entrance to the Rikers Island Correctional facility in New York. A report released Wednesday, Aug. 6, 2014 by the New York City Board of Correction stated that more than 90 percent of New York City jail inmates in solitary confinement aren't getting their legally mandated one hour of daily recreation time outside their cells. (Seth Wenig/AP)

AT NEW YORK’S Rikers Island, perhaps the most famous jail in the United States, “beatings are routine while accountability is rare,” Preet Bharara, the Justice Department’s lead attorney in Manhattan, said last week. Worse, Mr. Bharara was talking about the treatment of minors at the island lockup.

In the wake of a chilling Justice Department report, New York’s leaders have a lot to do to improve conditions at Rikers. But the rest of the nation should pay attention, too: The federal government is supposed to be setting a minimum standard of treatment for minors in the justice system. It is obviously falling short.

Following a New York Times investigation that found frequent abuse on the part of Rikers prison guards, the Justice Department last week released its own review. Federal auditors focused on a vulnerable subset of prisoners: minors aged 16 to 18, who are automatically charged as adults in New York. The result is a population of hundreds of teenagers, many with troubled home lives or mental illness, locked in a toxic and abusive environment ill-suited for the sort of rehabilitation that these young people need.

In recent years, there have been nearly as many instances of staff using force against prisoners — sometimes as “punishment or retribution,” and often in areas surveillance cameras don’t monitor — as there have been prisoners. Inmate-on-inmate fights are even more common. There are classrooms, but teachers say they are taught to avert their attention from beatings and other abuse that occur around them. A staggering number of teenagers at Rikers end up in the hell of solitary confinement, locked alone in a six-by-eight-foot cell for 23 hours a day, where they might get some instruction and guidance but only over the phone.

At least Rikers staff has tried to separate 16- to 18-year-olds from adult prisoners. But that has not been enough to create an environment suited to troubled, still-developing teenage minds. Staff need to be trained to avoid conflict in the face of belligerent teenage behavior. Instead, the guards assigned are apparently among the least experienced on the island. They need to impose a range of punishments to correct behavior. Instead, adolescents are thrown into solitary confinement for excessive amounts of time, which is associated with the development of paranoia, anxiety and depression.

The Justice Department recommended that New York put teenagers in a facility dedicated to housing them. That accords with the spirit of the Juvenile Justice and Delinquency Prevency Act , a 40-year-old federal law that demands that states refrain from housing juveniles in adult jails, even if adults and minors would be separated. Instead, presumably, states should be putting them in facilities attuned to dealing with minors. But the law doesn’t protect minors who have been charged as adults, as many are in New York and other states. Its baseline protections for juvenile prisoners also need some toughening.

Congress should end the act’s loophole, or at least close it tightly enough that only the worst sorts of minor offenders end up uncovered by federal juvenile detention requirements. Then it should bulk up those baseline standards.