MIKE LAWSON SPENT some 45 days in solitary confinement in a Nevada prison when he was 16 years old — the correctional facility’s way of keeping him safe from adult inmates. He was allowed out of his cell every three days to shower.

“This plays on your mind — not talking to anyone, not having anything to do,” he says. “To be honest, there were times when I thought about taking my own life.”

Mr. Lawson was one of the lucky ones who emerged alive and relatively unscathed. Now 21, he was released after serving a three-year sentence for robbery and works as a manager in a janitorial service and mentors other youth who have run into trouble.

Every day, some 10,000 juveniles are held in adult jails or prisons at an increased risk of rape and other forms of sexual abuse and violence. Others, like Mr. Lawson, are held in isolation and experience the emotional and psychological harm that comes from being cut off from human contact. For some, the strain is so intense that they commit suicide.

Although there are laws that call for most juveniles to be kept out of adult jails and prisons, these provisions do not go far enough. They do not, for example, address detention or incarceration protocols for youths charged or convicted as adults. The Justice Department has an opportunity to close these gaps, as Reps. Frank R. Wolf (R-Va.) and Robert C. “Bobby” Scott (D-Va.), lead sponsors of the Prison Rape Elimination Act (PREA), noted in a recent letter to Attorney General Eric H. Holder Jr. “The widespread consensus among correctional, mental health and juvenile detention organizations is that adult facilities are simply not equipped to safely detain youths,” they wrote.

The department is in the final stages of crafting rules to implement PREA, which was passed in 2003 to reduce the incidence of sexual abuse in jails and prisons. The department should include a rule prohibiting juveniles under 18 from being housed in adult facilities. On the rare occasions when this is impossible, the department should require that jails and prisons keep juveniles in separate housing units out of “sight and sound” of adult inmates until they can be moved to a juvenile facility. Solitary confinement should never be acceptable.