Overview

• The Supreme Court’s Second Small Bench, led by presiding judge Akira Ojima, issued the Sept. 26 judgment without referring the case to the Grand Bench, a move seen only once before since 2001.
• The lawsuits targeted a maximum 2.06-to-1 vote-value disparity, exemplified by Hokkaido No. 3 versus Tottori No. 1.
• Courts evaluated the Diet’s first use of the Adams method, which shifted districts with “10 increases and 10 decreases” across 15 prefectures, and high courts had uniformly deemed the framework reasonable.
• Two lawyer groups filed coordinated challenges in 14 high courts and branches seeking to void results, but the Supreme Court rejected their claims as it found the election constitutional.
• In a related case over the July upper-house vote, the Hiroshima High Court held its first hearing on Sept. 26 and set a verdict date of Oct. 31.