Each security officer in a prison usually deals with about 50 inmates, providing supervision and acting like their father. The intimate tie between the security officer and the inmates is the basis of the rehabilitation, medical, and educational treatment given in a prison. As the number of serious and habitual offenders has decreased, the role of the prison in separating them from the community has declined in importance. The rate of reported nontraffic offenses has declined in Japan over the past 30 years, probably due to the combined influences of economic development, increased education, the establishment of democratic institutions, the strength of informal social controls, and the success of formal social controls. The use of punishment and the role of prisons have undergone many changes since Japan's early history. As of 1980, over 95 percent of all convicted offenders were fined. Minor offenders were sentenced to fines or confinement of less than 30 days. Figures, data tables, and narratives present extensive additional statistics.