The parole system aims to promote smooth social reintegration of those inmates sentenced to imprisonment with or without work who evinces "genuine repentance" and are expected to rehabilitate themselves successfully by releasing them before their sentence completion and putting them on parole supervision for the rest of their imprisonment term.
  Parole may be granted to an inmate sentenced to imprisonment with or without work, after serving the statutory term, i.e. 1/3rd of the definite term of the sentence or 10 years of a life sentence (see Part 4, Chapter 2, Section 1, 4 (3) for special provisions under the Juvenile Act). With respect to "genuine repentance," the following four items are judged comprehensively: (1) whether he/she shows signs of remorse for his/her offense, (2) whether he/she shows a willingness to reform him/herself, (3) whether he/she shows no likelihood of repeating offenses, and (4) whether the sentiment of the society will approve him/her being granted parole. Parole is finally granted when it is deemed to be reasonable, based on those judgments, to put the inmate on parole supervision for his/her reform and rehabilitation.
  Probation offices exercising jurisdiction over inmates' next abode after release implement Environmental adjustment. On receiving a case history of an inmate from a penal institution, a probation officer or a volunteer probation officer in charge checks the planned location through interviews, etc. with a guarantor for making the environment suitable for rehabilitation of the released inmate.
  Cases for environmental adjustment have increased in accordance with an increase of inmates. In 2005, environmental adjustment was newly carried out for a total of 47,928 inmates, up by 3.2% from the previous year (Source: Annual Report of Statistics on Rehabilitation).