From the courtroom to the public: Judicial influence on People’s attitudes toward same-sex marriage in Japan

Can judicial action change public attitudes? While most empirical studies on the societal impact of court rulings have focused on the United States, particularly its Supreme Court, the influence of courts in other contexts remains largely unexplored. This study examines Japan—the only G7 country that does not legally recognize same-sex marriage—and explores how judicial rulings on same-sex marriage influence public attitudes. Using data from an original survey incorporating natural and experimental treatments, the analysis finds that while a court decision has no significant effect in a natural environment, experimental exposure to a reminder of the ruling can shift respondents’ views. The findings suggest that judicial action on same-sex marriage may have limited but measurable impacts on public attitudes, even in unconventional settings, and therefore contribute to discussions of external validity regarding the societal influence of courts.