The Hiroshima High Court and the Sendai High Court's Akita branch ruled Tuesday that last December's Lower House election was "in a state of unconstitutionality" due to the disparity in the weight of votes between districts.

But the courts rejected the plaintiffs' demand that the election results be nullified, citing the Diet's ongoing efforts to address the situation.

Two groups of lawyers have filed a total of 17 lawsuits over the vote-value disparity in the election. They have filed the suits with 14 high courts and their branches across the country.