Diet Must Continue to Tackle Issue Despite Top Court’s Constitutionality Ruling

The fact that the judicial decision came down on the side of constitutionality does not mean that the problems with the House of Representatives electoral system have been resolved. Both the ruling and opposition parties should hold ground-up discussions on the very nature of the system.

The Supreme Court’s Grand Bench ruled that the 2021 lower house election, in which the maximum vote-value disparity was 2.08-to-1, was constitutional, noting that “the disparity will be corrected under a new system, and cannot be said to have been in a state of violating the equality of voting values.”

The top court’s ruling recognized the Diet’s efforts to correct the disparity, including its decision in 2016 to introduce the so-called Adams method in which population ratios are better reflected in the allocation of Diet seats. The 2021 lower house election was held amid the government’s review of a redistribution of seats.

The top court ruled that the 2009, 2012 and 2014 lower house elections, in which the disparities exceeded 2-to-1, were in a state of unconstitutionality. The 2017 lower house election, when the disparity was 1.98-to-1, was ruled constitutional. In recent years, whether the disparity exceeds 2-to-1 has been regarded as the standard for determining whether an election is constitutional or in a state of unconstitutionality.

In the 2021 lower house election, the disparity slightly exceeded 2-to-1, but the top court’s ruling acknowledged that natural population movement was a factor behind the disparity and “the extent of the disparity was not significant.”

It is appropriate that the top court did not make a rigid judgment based solely on the numerical value of the disparity, and recognized the broad discretionary power of the Diet.

However, it is true that the current electoral system has various problems.

Last year, the revised Public Offices Election Law was enacted to redistribute seats, taking 10 seats from 10 prefectures and adding 10 seats to five other prefectures, based on the Adams method. The revised law will be applied from the next lower house election.

The legal revisions redistributed a record number of 140 constituencies in 25 prefectures. As a result, the maximum disparity will be reduced to 1.999-to-1.

The disparity will keep widening as the nation’s population continues to flow from rural to urban areas. If the Diet persists in equalizing vote values and significantly reviews a redistribution of seats each time, lawmakers and voters will both be confused.

The continuing decline in the number of lawmakers in regions could shake the system of representative democracy, in which voters elect lawmakers to whom they entrust the steering of the national government.

The current electoral system comprising a combination of single-seat constituencies and proportional representation, in which a candidate can run for both sections, has some problems. The “revival victories” in proportional representation segments by candidates who lost their single-seat constituency race is one such example.

The lower house special committee that debated the 10-seat increase and 10-seat decrease proposal has adopted a supplementary resolution to hold in-depth discussions at the Diet regarding the number and redistribution of Diet seats. The ruling and opposition parties must not break that promise.

The House of Councillors has introduced an integrated constituency combining two neighboring prefectures, but voter turnout has been on the decline in the targeted prefectures.

Both chambers of the Diet need to work together to sort out their respective roles and eliminate the inadequacies of the electoral systems.

(From The Yomiuri Shimbun, Jan. 26, 2023)