In May 2006, the government revised the prison law in the first attempt at broad reform since 1908. The Law Concerning Penal Institutions and the Treatment of Sentenced Inmates, as the legislation is formally known, went into effect June 7.

The prison system has long been criticized by not only the United Nations and other governments but also domestic and international human rights groups, lawyers and law enforcement officials for violating the basic human rights of inmates and for cruel and unusual punishment, including torture.

Well-documented accounts of prisoner abuse by police and prison guards are legion. Experts say that unlike prisons in other countries, where the goal is often to rehabilitate and re-educate, the primary purpose of Japanese prisons is to force inmates to reflect on their misdeeds.