A law to revise lower house electoral districts to reduce voting weight disparities between densely and sparsely populated constituencies took effect Sunday following a monthlong period to notify the public about the changes. The revised Public Offices Election Law reduced the number of lower house members elected from Aomori, Iwate, Kagoshima, Kumamoto, Mie and Nara prefectures by one each, with another four seats cut from proportional representation blocks, shrinking the lower house to a postwar low of 465 seats. The amendment brings the maximum vote weight disparity between districts down to 1.999 to 1 — just under the 2-to-1 threshold that the Supreme Court has said would undermine the Japanese Constitution’s guarantee of equality for all under the law.
As a result of the reform, the disparity is expected to fall below the threshold over the next three years.
In line with a lower house election reform law enacted last year, the districts are expected to be revised again after the results of a 2020 census are released, introducing a different seat apportionment method to more accurately reflect population differences between prefectures.