Despite a federal law that prohibits the incarceration of youth in adult correctional facilities, the number of young people held in jails across the country has exploded by 208 percent since the 1990s, according to a new report released today at the national press club by the Campaign for Youth Justice. States exploit a loophole in federal law, which was designed to protect youth from the proven dangers of adult jails but only applies to youth in the juvenile justice system.