Holding signs showing vote-value disparities of electoral districts, lawyers march to the Tokyo High Court to file a lawsuit seeking the nullification of the July 21 Upper House election results. (Eri Niiya)

Two groups of lawyers have filed lawsuits across Japan to nullify results of the July 21 Upper House election, saying vote-weight disparities violated the constitutional guarantee that people are equal under the law.

They also argued that the Diet’s 2018 legal revisions, which were pushed by the Supreme Court and were supposed to rectify the recurring vote-disparity problem, failed miserably in its purpose.

“Does the top court feel that the disparity is constitutional even though the Diet is outrageously disrespectful of it?” said Hidetoshi Masunaga, a lawyer with a group that filed 14 lawsuits. “The court is on the brink of losing its worth by abandoning the constitutional principle of separation of powers.”

In the suits filed at the high court level on July 22, the lawyers pointed out that the lowest preliminary number of voters per Upper House seat on election day was about 650,000 in the electoral district of Fukui Prefecture.

In contrast, the highest number of voters per seat was about 1.94 million in the electoral district of Miyagi Prefecture.

That means, one vote in the Fukui Prefecture district was worth three in Miyagi Prefecture.

The preliminary figures for voter numbers as of July 21 were released by the Ministry of Internal Affairs and Communications.

The focus of the lawsuits will be on whether the high courts view a disparity of 3.00 times as a validation of the Diet’s 2018 revisions of the Public Offices Election Law.

The Supreme Court concluded that the Upper House election in 2010, which had a maximum vote disparity of 5.00 times, and the Upper House poll in 2013, with a maximum disparity of 4.77 times, were held “in a state of unconstitutionality.”

In response to the ruling, the Diet introduced a system that combined the electoral districts of Tottori and Shimane prefectures and those of Tokushima and Kochi prefectures before the Upper House election in 2016.

As a result, the maximum disparity decreased to 3.08-fold, and the Supreme Court decided that disparity was constitutional.

One reason for the top’s court decision was that an additional clause in the revised Public Offices Election Law stated that the Diet “will continue to conduct a sweeping review toward the Upper House election in 2019 and draw a conclusion by all means.”

In line with the 2018 revisions, the Diet introduced a system to add six seats to the Upper House to reduce the disparity.

Of the six, two were added to the electoral district of Saitama Prefecture, which had a large vote-disparity compared with the least populous district in Japan.

But the remaining seats were assigned to the proportional representation segment as a relief measure for candidates who could not run because of the merger of electoral districts. This allotment drew wide criticism as having nothing to do with rectifying the vote-value problem in electoral districts.

The lawyers group led by Kuniaki Yamaguchi filed a lawsuit at the Hiroshima High Court concerning the vote-value disparity of the electoral district of Hiroshima Prefecture.

The group plans to file a similar suit at the Tokyo High Court concerning electoral districts in heavily populated Tokyo and Kanagawa Prefecture, where the vote disparities were 2.94 times and 2.96 times, respectively.

The high courts are expected to deliver verdicts by the end of this year. The Supreme Court will likely hand down a unified judgment in the cases next year.