The Sendai High Court's Akita branch ruled Thursday that the disparity of up to 4.77 times in the weight of votes in July's upper house election was "in a state of unconstitutionality," but rejected the plaintiffs' demand that the election results in the Akita constituency be nullified.
The ruling was the last of similar lawsuits filed with 14 high courts and their branches across Japan by groups of lawyers.
Presiding Judge Yasuhiro Kuga said the vote-value gap in the July House of Councillors election was in a state of unconstitutionality but the gap was not unconstitutional as it cannot be said that parliament neglected to correct the gap in a reasonable period of time under the Constitution.
In the trial, the defendant, the Akita prefectural election board, said it would take a reasonable period of time to fundamentally reform the electoral system, calling for the rejection of the plaintiffs' demand.
The Hiroshima High Court's Okayama branch has ruled that election results in the Okayama constituency should be invalidated due to an unconstitutional disparity in the weight of votes.
The Osaka High Court and the Tokyo High Court have found the vote-value gap unconstitutional, while the 10 other courts ruled the disparity was in "a state of unconstitutionality."
In October last year, the Supreme Court ruled the maximum disparity of five times in the weight of votes in the 2010 upper house election was "in a state of unconstitutionality" and called on the legislature to carry out fundamental reform.
However, the vote-weight disparity only slightly fell to 4.77-fold in the July election as a result of minor amendments to the election law in November last year. The revised election law states that deliberations on fundamental reform of the electoral system should be conducted before the next upper house election in 2016.
The disparity in the number of eligible voters per upper house member stood at 4.77-fold between the Hokkaido constituency, which has the most voters, and the Tottori constituency, which has the fewest.
The gap was 1.89-fold between the Akita constituency and Tottori, according to the lawsuit in Akita.