During the period from1945to1954,the aim of prison administration was prisoners'rehabilitation and reintegration into society under the new Constitution.In reality,however,prisons faced various difficulties such as the rapid increase in prisoners amidst the post-war chaos,defects in prison facilities and equipment due to war damage and aging,and extreme lack of resources,suffering the frequent occurrence of mass prison breaks,riots,and revolts.
  Since the beginning of the period of high economic growth from1955to1974,the crime situation became gradually stable,which helped to ease prison overcrowding and restore order therein.During this period,efforts were sustained to achieve"correction and treatment of prisoners for their reform and social rehabilitation,"and improvements were made.
  More specifically,in order to promote and improve the Classification Treatment System,the first classification center was established in the Nakano Prison as a special institution for prisoners'diagnosis and classification(in1957),and the new Regulation on Vocational Training for Convicted Prisoners(Minister of Justice Ordinance)was enacted for the purpose of enabling prisoners to obtain various qualifications such as in hairdressing and car mechanics(in1956).Vocational training was provided for selected prisoners in the course of prison work,so as to nurture willingness to work in them and allow them to obtain qualifications that will be helpful for finding jobs after the release from prisons.The Open Treatment System started to handle the rapid increase in prisoners convicted for traffic offenses(in1961),and the Ichihara Prison was established as a prison specializing in this new treatment system(in1969).It is also based on the philosophy of"individualization of treatm ent,"aiming to promote rehabilitation and reintegration into society of prisoners by treating them according to their individual needs.
  In1972,the Rule for the Classification of Convicted Prisoners(Minister of Justice Ordinance)was established as an advanced version of the Guideline for Prisoners'Diagnosis and Classification established in1948.The new Rule intended to"promote rehabilitation and reintegration into society"of prisoners through the classification treatment,and introduced the classification category of treatment in addition to the conventional classification category of allocation.It also provided for the establishment of a classification center in each of eight Regional Correction Headquarters nationwide.
  During this period,various other measures were taken to improve the treatment of prisoners in their daily lives through the amendment of the Prison Law Enforcement Regulations,such as the reduction of the period for solitary confinement,relaxation of the prohibition of chat,lifting of the prohibition of the use of tatami flooring in prison cells,lifting of the prohibition of access to ordinary newspapers,and permission of hairstyles other than close-cropped hair(in1966).