Japan’s Agenda Setting to Lower the Voting Age from 20 to 18: Prioritizing Constitutional Revision over Democratic Legitimacy

What age a state designates as appropriate for voting rights raises a range of democratic and empirical issues. The lowering of the voting age in Japan in 2015 was the biggest expansion of the country’s democratic franchise since 1945, yet it happened in an abrupt manner. Lowering the voting age was not a significant issue among the Japanese public until the mid-2000s and the government began supporting the move officially only in 2014. Why then? What happened to precipitate this decision? This study argues that the circumstances governing the period before the policy decision was made are crucial to understanding what followed. In the prevailing theories of policy change, analysis has focused much more on the phase of decision making over policy; public opinion, policy beliefs, and policy transfer have been prominently cited as the major reasons for lowering the voting age in other countries. In contrast, this article claims that the policy opportunity spillover, from constitutional revision to voting age, was a necessary condition for lowering the age. The discussion of constitutional revision incidentally opened a policy window to another issue area, in this case voting age. The findings help us answer the question of what time period we need to examine in order to discern actual policy dynamics.