The Supreme Court ruled on Nov. 18 that the 2019 Upper House election was constitutional and rejected calls for a do-over, despite the large vote disparity between urban and rural districts.

But, at the same time, the top court said the Diet still needs to do more to reduce the disparity produced by the electoral system.

Two groups of lawyers had filed separate lawsuits asking that the election results be tossed out and be redone because a vote in the district with the fewest voters for an Upper House member carried three times the weight of a vote in the district with the most votes per Upper House member.

One of the legal groups hailed the ruling as a “major step” in the right direction, as it prods lawmakers to take further steps toward reducing the disparity, but the other group said it falls short of addressing the problem.

The Supreme Court said in its ruling that major progress had not been made in resolving vote disparity. But it still ruled the election was constitutional, based mainly on the fact that the Diet kept a new measure in place, first introduced in the 2016 Upper House election, that combined two prefectures into a single district.

The Supreme Court ruling pointed out that the combined districts had reduced the vote-disparity gap, which had been about a fivefold gap for decades, to 3.08 times.

Some lawmakers had called for doing away with the combined district system because it resulted in a lower turnout. But the Supreme Court said keeping the measure in place for the 2019 Upper House election was a major factor in deeming it constitutional.

The top court also chided the Diet for failing to keep its pledge when it revised the Public Offices Election Law in 2015 to introduce the combined-district provision. The legislation had said that “further comprehensive revisions” would be made to reduce vote disparity.

But the government only made one change for the 2019 Upper House election, when it increased the number of seats in the Saitama prefectural district by two. The Supreme Court said that change was far from the comprehensive revision it had expected, but the lack of more measures was not enough to tip the scales.

“We cannot conclude that (the Diet) has given up its stance of seeking to correct the disparity,” the court ruling said.

The ruling concluded that the threefold disparity “could not be considered unequal to the extent of creating a constitutional problem.”

The majority opinion included 10 of the 15 justices, but three justices issued dissenting opinions that the 2019 Upper House election was unconstitutional.

Justice Keiichi Hayashi used a government spending analogy in describing the vote disparity.

“For example, if residents in one prefecture received three times the outlays of another prefecture, voices would be raised about the unequal nature,” Hayashi wrote.

He also expressed concern that the ruling might lead to the three-fold disparity continuing permanently.

Justice Yuko Miyazaki also ruled the election was unconstitutional and said she could not find any elements that made her confident the Diet was moving toward a comprehensive revision.

Justice Mamoru Miura wrote that the election was in a “state of unconstitutionality.”

Justice Koichi Kusano meanwhile used an entirely different argument to rule that the election was constitutional.

The Supreme Court heard appeals arising from 16 lawsuits filed in high courts and branches around Japan. The Takamatsu and Sapporo high courts ruled that the 2019 election was held in a state of unconstitutionality, while the other 14 rulings said the election was constitutional.

The two groups of lawyers that filed the lawsuits had vastly different appraisals of the Supreme Court ruling.

One group, which included lawyer Hidetoshi Masunaga, said the ruling was “a major step forward.”
Makoto Ito, a member of the group, said the ruling “called on the Diet to make further efforts” to reduce vote disparity.

But the other group of lawyers, including Kuniaki Yamaguchi, said the ruling should have searched for the reason behind the extreme inequality in the current system and added that the standards used by the Supreme Court were far removed from the thinking of ordinary citizens.

However, experts cautioned that vote disparity is not an issue that only falls in the hands of the Supreme Court to resolve.

“The ruling said there was a need to maintain a stance of working toward revision,” said Toru Mori, a professor of constitutional law at Kyoto University. “So the ruling should not be seen as accepting the current situation as is.”

But Harukata Takenaka, a political science professor at the National Graduate Institute for Policy Studies, criticized the ruling for allowing inequality in the vote to remain.

Takenaka said drastic measures are needed to change the Upper House electoral system to reduce vote disparity.

(This article was compiled from reports by Shunsuke Abe, Eri Niiya, Takahiro Okubo and Wataru Netsu.)