Event Report: Surnames and Same Sex Marriage: Constitutional Litigation in Japan
On September 3rd 2025, the Centre for the Study of Global Japan (CSGJ) launched the 2025-26 academic year with its first event: “Surnames and Same Sex Marriage: Constitutional Litigation in Japan.” This event featured Professor Colin P.A. Jones of Doshisha University Law School, who presented his research on constitutional litigation in Japan.
Professor Jones began the presentation by introducing his own scholarly background. Though he did not begin studying Japanese until the age of 18, he managed to write his first four books in Japanese, an impressive and inspiring takeaway for language students in the audience. He then introduced the topic of constitutional litigation in Japan, highlighting some recent headlines that have drawn attention to the topic, namely those concerning the topics of same-sex marriage bans and dual surnames.
Jones then provided background information on the Supreme Court and the legal system in Japan. Observing that in the past 80 years, the Supreme Court has only found statutory provisions to be unconstitutional thirteen times, he noted that the court is often viewed as “conservative.” He then outlined intriguing variation in the topics of these cases, which ranged from the allocation of seats in the House of Representatives to the handling of special delivery mail. He then discussed the context of lawmaking and the judiciary in Japan to further contextualize the research. Within this overview, Jones also addressed ongoing scholarly debates concerning the role of Japanese bureaucrats and LDP politicians in lawmaking.
Jones then categorized the thirteen cases into various groups, such as criminal cases and voting rights cases, to further analyze the outcomes. By examining the cases through different groupings, he offered different lenses for understanding each decision and raised new insights about the Japanese Supreme Court’s notion of constitutionality.
Finally, the presentation concluded by returning to the opening issue: the recognition of same-sex marriage in Japan. Japan has historically provided less recognition to the rights of same sex couples compared to most Western countries. However, Jones emphasized that many local governments have begun to rapidly recognize these partnerships, and he discussed the potential role the Supreme Court might play in the future. The presentation was followed by a lively Q and A session moderated by Phillip Lipscy, director of the Centre for the Study of Global Japan, with enthusiastic participation from many audience members.
The Centre of the Study of Global Japan would like to thank Professor Colin P.A. Jones for his insightful discussion of Japanese legal issues and the audience for their thoughtful engagement in the discussion.
