NASHVILLE (AP) — A federal judge on Thursday issued a preliminary injunction barring a Tennessee County from putting juvenile offenders in solitary confinement.

The court's decision comes amid a class-action lawsuit against Rutherford County and the Tennessee Department of Children's Services that was originally filed last year on behalf of a 15-year-old. The lawsuit alleged the boy was held in isolation in a concrete cell for 23 hours a day.

In an opinion dated Wednesday, U.S. District Judge Aleta Trauger said putting juveniles in solitary confinement was cruel and inhumane punishment.

"Specifically, the Court finds that Plaintiffs have shown that they are likely to succeed on their claims that juveniles being detained in solitary confinement or isolation for punitive or disciplinary purposes constitutes such inhumane treatment," Trauger wrote.

The opinion also said the "Rutherford County defendants have produced a list of 128 juveniles who experienced isolation for punitive or disciplinary reasons from March 17, 2016, through October 7, 2016."

An attorney for the 15-year-old boy who was the subject of the original lawsuit last year said his client was pleased with the judge's order.

"It's his hope that through this case that no other children in Rutherford County or the state of Tennessee will have to endure solitary confinement as punishment," attorney Wesley Clark said. The American Civil Liberties Union is also involved in the case.

Phone and email messages with the Rutherford County attorney's office weren't immediately returned. Officials with DCS and the state attorney general's office also did not immediately respond to emails seeking comment.

Most of the juveniles in the detention center are awaiting trial and yet to be found guilty, Clark said. He said his client was in the center while awaiting trial on an aggravated robbery charge when he was put in solitary confinement for acting up in class, talking when he wasn't supposed to and flashing gang signs. Nothing he was accused of doing, Clark said, was ever a threat to the facility or anyone there.

Rutherford County puts the kids alone in a room with a boarded window and nothing but a Bible. At night, they bring the kids bedding.

"They don't want to call that solitary confinement," Clark said.

An attorney working with the ACLU applauded the judge's decision.

"Being locked in a concrete cell alone for 23 hours a day with nothing but a mattress and a toilet can create lasting damage for a young person's psychological, social and physical development," said ACLU-TN cooperating attorney Mark J. Downton in a statement. "We are pleased that the court has recognized that subjecting young people to solitary confinement for disciplinary purposes is inhumane."