Number of Juveniles Held in Adult Jails in the US

"About 4,200 juveniles age 17 or younger were held in local jails at midyear 2014. They accounted for 0.6% of the confined population, down from 1.2% at midyear 2000. Nearly 90% or 3,700 juvenile inmates were tried or awaiting trial in adult court. The number of juveniles not charged as an adult declined by 74% between midyear 2010 and 2014 (from 1,900 to 500 inmates)."

Source: 

Todd D. Minton and Zhen Zeng, PhD, "Jail Inmates at Midyear 2014," Bureau of Justice Statistics (Washington, DC: Department of Justice, June 2015), NCJ248629, p. 4.
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