For the third time in a row, the Supreme Court has ruled that the disparity in the value of votes between populous and less populous constituencies in a Lower House general election was so wide that it violated the principle of equality guaranteed under the Constitution. Though again falling short of ruling the election results invalid, the top court decision on the December 2014 election should be taken as a clear denunciation of lawmakers' failure to fundamentally correct the regional imbalance in the power given to voters in choosing representatives to the Diet. Members of the Diet must not take the court ruling as a reprieve but as a stern warning against their negligence to take action.

In ruling Wednesday on a set of lawsuits filed by lawyers seeking to invalidate the outcome of Lower House races in 295 single-seat districts in the 2014 election, the Supreme Court determined that the election — in which the maximum gap in the value of votes reached 2.13 to 1 — was held in a "state of unconstitutionality" but declined to rule the election invalid. Three of the 14 justices said the election was "unconstitutional," including two who asserted that the outcome should be invalidated.

It was the same judgment handed down regarding the two previous Lower House elections — the August 2009 poll that brought the Democratic Party of Japan to power, in which the vote value gap hit as much as 2.30 to 1, and the December 2012 election that saw the Liberal Democratic Party's return to the helm of government, in which the disparity grew to as wide as 2.43 to 1.