The Introdiction of Jury Systems in Japan: A Comparative Study

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K03267
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Politics
• Research Institution: The University of Tokyo
• Principal Investigator: Kage Rieko 東京大学, 大学院総合文化研究科, 准教授 (10362807)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 比較政治 / 裁判員制度 / 司法政治 / 陪審制 / 参審制

Outline of Final Research Achievements

This study sought to explain the introduction and design of new jury/lay judge systems from a comparative perspective. Jury or lay judge systems typically transfer powers regarding verdict and sentencing from professional judges to citizens, but to varying degrees in different countries. The study showed that in terms of "transfer of powers" from professional judges to citizens, Japan lies in between Spain and South Korea, both of which also introduced new systems of participation in criminal trials in recent years. The study drew on analyses of fifty years of Japanese parliamentary debates as well as careful case studies of Japan, South Korea, Spain, and Taiwan, to demonstrate that the difference in the extent to which countries chose to transfer powers from professional judges to the citizens may be explained by the different configurations of party politics in these countries, particularly by the preferences and relative power of "new left"-oriented parties.

Free Research Field

比較政治学

Academic Significance and Societal Importance of the Research Achievements

司法分野をめぐる政策決定は、すぐれて政治的・政策的であるにも関わらず、わが国政治学では十分に考察されてこなかった。わが国の司法部門は独立性が低いといわれるが、古くは公害訴訟や、近年の一連の薬害訴訟判決などをみても、司法が政治・行政に重要な影響を与えることは少なくない。アメリカ政治学においては、司法と政治・行政の間の関係について、様々な理論化が試みられてきたが、大統領制と、わが国のような議院内閣制では三権の間の関係も質的に異なる。本研究は、わが国の政治・行政・司法の間の関係について理論化を試みるだけでなく、議院内閣制諸国一般における三権の間の関係についても理論化に繋がる枠組みを示すものである。