Vote-Value Gap Tops 2 Times in 16 Japan Lower House Districts

Tokyo, July 29 (Jiji Press)–Sixteen single-seat constituencies for Japan’s House of Representatives, the lower chamber of parliament, have a vote-value gap of over two times compared with the least populated district, Jiji Press estimates showed Wednesday. The number rose from eight in 2024 and 12 in 2025, according to the estimates compiled on the basis of population data as of Jan. 1 released by the internal affairs ministry the same day. The largest gap is 2.139 times, larger than 2.103 times in 2025. A gap of two times is believed to be a benchmark used by Japan’s Supreme Court in ruling whether Lower House elections are constitutional in terms of vote-value disparities. The government’s council on Lower House electoral districts has started work to rezone constituencies for the chamber to reduce the maximum gap to less than two times, planning to submit its proposal by May next year. The largest gap is between the No. 3 constituency in Ishikawa Prefecture, with a population of 255,671, the least among all 289 Lower House constituencies, and the No. 5 constituency in Fukuoka Prefecture, with the largest population of 546,962. The gap stands at 2.125 times for the second most populous Fukuoka No. 3 constituency and 2.107 times for the No. 6 constituency in Ibaraki Prefecture, which has the third-largest population. This year, the vote-value gap newly topped two times in the No. 1 constituency in Fukuoka, the No. 1 constituency in Miyagi Prefecture, the No. 3 constituency in Kanagawa Prefecture and the No. 1 constituency in Hokkaido. For the House of Councillors, the upper chamber, the vote-value disparity topped three times in three prefectural constituencies compared with Fukui Prefecture, which has the least per-seat population of 359,310. The largest disparity of 3.091 times is logged in Kanagawa, with the largest population of 1,110,614 per seat. The gap is 3.083 times for Tokyo and 3.029 times for Miyagi. END [Copyright The Jiji Press, Ltd.]