High courts have ruled that the House of Councillors election held this past July, in which the value of one vote in the most sparsely populated constituency was 3.08 times that in the most densely populated district, was "in a state of unconstitutionality" in 10 of 16 lawsuits.
The election was held under a new electoral system that was established after the Public Offices Election Act was revised last year, in which the neighboring Tottori and Shimane prefectural constituencies have merged into one and the Tokushima and Kochi electoral districts have also been amalgamated.
The focal point in the 16 trials was how the courts would evaluate the Diet's efforts to rectify the vote value disparity through the mergers of these four prefectural constituencies into two.
The maximum vote value disparity in the previous upper house election in 2013 was 4.77. It is of great significance that 10 high courts and high court branches concluded that the Diet's efforts to rectify vote value disparity were insufficient although the mergers have substantially reduced the maximum gap in vote values. These rulings have urged the legislature to further narrow the gap.
The Supreme Court earlier ruled that vote value disparity in the 2013 poll was in a state of unconstitutionality, pointing out extreme inequality in the value of votes. A state of unconstitutionality refers to a situation in which vote value disparity cannot be immediately deemed as unconstitutional but can be recognized as such unless the gap is rectified sufficiently within a rational time frame. In the ruling, the top court pointed to the need for the Diet to take legislative measures to eliminate the inequality as swiftly as possible.
The recent rulings on the July upper house race were divided over their evaluation of the Diet's revisions to the Public Offices Election Act to narrow vote value disparity. For example, the Okayama branch of the Hiroshima High Court, which ruled that the July poll was in a state of unconstitutionality, concluded that the gap remained over three times because the legislature focused on ensuring each prefecture had one constituency and as a result minimized the number of prefectural constituencies merged with others.
In contrast, the Tokyo High Court, which declared that the election was constitutional, favored the fact that the revisions to the law have substantially reduced the maximum gap, which had remained at nearly five times over several decades.
The Akita branch of the Sendai High Court stated that the court cannot justify a gap three times the difference, even considering that upper house members serve as representatives of regional communities.
It is the Diet's role to consider how to use these rulings to correct the gap in vote values. The Supreme Court has recognized that the Diet has broad discretionary power over how to rectify vote value disparity, while warning the inequality in the value of one vote.
Voter turnout declined to the lowest level in history in three of the four prefectures affected by the merger, except Tottori Prefecture, highlighting problems with the mergers of prefectural constituencies.
Considering the roles of the upper chamber, it is not necessarily irrational to consider an electoral system based on the current framework centering on prefectural constituencies. However, it is no easy task to reduce vote value disparity while maintaining the prefectural constituency system.
Some within the ruling Liberal Democratic Party are calling for the elimination of merged prefectural constituencies of the Tottori-Shimane and Tokushima-Kochi districts. However, such reform would not lead to a fundamental resolution to the gap in vote values. Without substantive debate on the division of roles between the lower and upper houses and the raison d'etre of the upper chamber, no fundamental resolution could be found. Ruling and opposition parties should overcome the influence of their partisan interests and hold constructive discussions.
A bylaw attached to the revised Public Offices Election Act states that the Diet must fundamentally review the electoral system and draw a conclusion in time for the 2019 upper house race. The Diet needs to begin discussion on the issue promptly without waiting for a ruling on the July election by the Supreme Court.