Correctional institutions include prisons, juvenile prisons, and detention houses. Prisons and juvenile prisons are institutions whose principal role is to house offenders sentenced mainly to imprisonment with labor, imprisonment without labor, or penal detention for the execution of their sentences, and to administer the necessary treatment to these offenders. Detention houses are institutions that mainly house detainees awaiting trial(that is, defendants and suspects remanded in custody;the same applies below).
  As of April 1 st, 2000,correctional institutions numbered 74 institutions proper (59 prisons, 8 juvenile prisons, and 7 detention houses) plus 116 branch institutions (6 branch prisons and 110 branch detention houses).
  As of December 31st, 1999, the detention capacity of correctional institutions was 64,164 inmates (including 48,256 convicted inmates) while the actual number of detained inmates was 56,133 (including 45,606 convicted inmates). The detention rate (the ratio of actual inmates to detention capacity) was thus 87.5% overall and 94.5% for convicted inmates(source:Correction Bureau, Ministry of Justice). Staff employed at correctional institutions are prison officers (Justice Ministry officials with custodial authority under the Prison Law), Justice Ministry technical officers, and Justice Ministry education officers.
  The existing Prison Law was enacted in 1908 but has not been substantially amended since then. It is therefore outdated in both form and content, and numerous related ordinances, directives, notifications, etc., have been issued, making prison-related legislation complex and difficult to understand. Thus, studies are now underway towards a complete amendment of the Prison Law, with a view to the appropriate management and running of prisons, detention houses, etc., and vastly improving the treatment of detainees in every aspect. This includes clarifying the rights and obligations of inmates, appropriate treatment befitting the legal status and special character of inmates, and development of a system that will contribute to the reform and rehabilitation of inmates.