Comparative analysis is crucial to academic studies of public administration because it provides understanding of the nature of different types of public service institution: in particular, it helps to show what they do and don’t have in common, what kinds of institution they are, and what kinds of problems they face. However, in order to effectively conduct comparative research of public service institutions it is important that some thought is given to how they can best be compared. Accordingly, it is argued in this study that the differences between public service institutions can be appropriately analysed by examining their respective risk control cultures. This study makes use of the grid and group cultural theory, as developed by Mary Douglas, Aaron Wildavsky and Christopher Hood, to analyse the risk control cultures of the English and Japanese prison services in regard to two specific types of risk, namely suicide and violence. The results show that particular patterns of organizational behaviour within the English and Japanese prison services can be identified with their respective risk control cultures. More specifically, the English prison service tends to try to control risk by using formal rules and granting strong leadership roles to governors. By contrast, the Japanese prison service tends to use informal rules and group pressures to control risk. Furthermore, the peculiar organizational patterns of risk control within both organizations are often not recognised by their members. As a result, the strengths and weaknesses of organizations can be identified by analysing the patterns of risk control behaviour within them.

In Japan, the prison population has been aging at a pace far exceeding the general population. This rapid aging has increased the costs in all aspects of prison administration, which has become a great burden on the Japanese prison system. However, little has been clear about the causes of the current explosion of elderly prisoners. This study explores factors affecting the aging prison population, and examines the extent to which three main possible causes affect the aging prison population: the elderly population growth in general society, increased criminal behavior of elderly people, and legal harshness by the criminal justice organizations, such as kinds of sentences and lengths of imprisonment. This study adopts a longitudinal design, using three kinds of cross-sectional annual data sources aggregated for the whole country of Japan during 20 years from 1988 to 2007. The findings indicate that while the the non-elderly prison population growth has been caused by harsher legal attitudes, the main reason for the elderly prison population growth is increased criminal behavior itself.