Adult correctional facilities

Prisoners under legal authority of state or federal correctional authorities who are housed in prison facilities (e.g., prisons, penitentiaries, and correctional institutions; boot camps; prison farms; reception, diagnostic, and classification centers; release centers, halfway houses and road camps; forestry and conservation camps; vocational training facilities; prison hospitals; and drug and alcohol treatment facilities for prisoners), regardless of which government entity physically holds them. This number also includes prisoners who are temporarily absent (fewer than 30 days), out to court, or on work release; housed in local jails, private facilities, and other states or federal facilities; and serving a sentence for two jurisdictions at the same time. This count excludes prisoners held in a state or federal facility for another state or the Federal Bureau of Prisons (BOP). However, prisoners housed in another state and under the legal authority of the governing state are included.

Compared to jail facilities, prisons are longer-term facilities owned by a state or by the federal government. Prisons typically hold felons and persons with sentences of more than a year; however, the sentence length may vary by state. Six states (Connecticut, Rhode Island, Vermont, Delaware, Alaska, and Hawaii) have an integrated correctional system that combines jails and prisons. There are a small number of private prisons, which are facilities run by private prison corporations whose services and beds are contracted out by state or federal governments.