"The Bureau of Prisons (BOP) was established in 1930 to house federal inmates, professionalize the prison service, and ensure consistent and centralized administration of the federal prison system. The BOP is the largest correctional agency in the country, in terms of the number of prisoners under its jurisdiction. The BOP must confine any offender convicted and sentenced to a term of imprisonment in a federal court. All BOP correctional facilities are classified according to one of five different security levels: minimum, low, medium, high, or administrative. An inmate's designation to a particular institution is based primarily on the level of security and supervision the inmate requires; the level of security and staff supervision the institution is able to provide; and the inmate's program needs. All inmates undergo a comprehensive intake screening when they are admitted to a BOP facility. The BOP provides health care for all inmates either through each prison's ambulatory care clinics or by contracting for services through local hospitals. The BOP also provides mental health treatment to inmates who demonstrate a need for it through staff psychologists. The BOP has an established inmate disciplinary system, whereby sanctions are imposed on inmates for committing prohibited acts. An inmate is allowed to request a review of his or her conditions of confinement through the BOP's Administrative Remedy Program. Inmates have access to a variety of rehabilitational programs including education programs, substance abuse treatment, vocational education, and work opportunities. In order to help aid an inmate's transition back into the community, inmates can be placed in a Residential Reentry Center (i.e., a halfway house) for a period of time before their sentence expires."
CRS Report for Congress, R42486