A national group that studies prison systems called Wednesday for widespread reforms within Florida's juvenile-justice system.

The National Council on Crime and Delinquency said the state is locking up far too many young offenders, then failing to properly provide for their health and mental well-being.

The state could safely divert 21,000 juvenile offenders a year -- 40 percent of its detention-center population -- to their homes or programs that don't operate like jails, and if it did, Florida would save $26 million a year, according to a two-year, 38-page study released Wednesday by the nonprofit organization.

The group also criticized the Florida Department of Juvenile Justice, the state agency that runs the detention centers, for allowing the facilities to become crowded, providing spotty medical care and placing too many -- 40 percent of the population it surveyed -- in solitary confinement.

"Now is the time for Florida to substantially reform its juvenile-detention programs," wrote authors Barry Krisberg, president of the nonpartisan, nonprofit group based in Oakland, Calif., and researcher Vanessa Patino.

"Conditions in some Florida detention facilities are unacceptable and possibly expose the state to litigation," they wrote.

An Orlando Sentinel investigation, published in 2004, found more than 600 confirmed cases of child abuse or neglect at juvenile-justice department facilities from 1994 to 2004.

Department of Juvenile Justice spokesman Tom Denham said the same thing about Wednesday's study as he did after the Sentinel investigation: Researchers based findings on outdated information.

He said the department is locking up fewer young offenders now than in the 1990s, despite an increase in the number of young people living in Florida.

Denham also said much of the new study was based on the uncorroborated accounts of juvenile criminals.

The study's researchers began interviewing offenders in the state's 26 juvenile-detention facilities -- the equivalent of county jail for minors -- in 2003, when the department was in crisis. The department was under investigation by two grand juries as well as a state legislative committee.

In spring and summer 2004, the state began to remake the juvenile-justice department. It fired more than a dozen department employees, and its top two officials took leaves of absence from which they never returned.

In May 2004, Gov. Jeb Bush appointed a new department secretary, Anthony Schembri, a reformer who has worked to stop violence within department facilities and to improve medical care.