The re-demarcation of Lower House electoral districts proposed by a government council to Prime Minister Shinzo Abe last week would be the most sweeping one since the current electoral system was introduced in the mid-1990s, redrawing the borders of a total of 97 single-seat constituencies in 19 prefectures. It's part of a scheme to narrow the disparity in the value of votes between populous and less populous districts — which hit 2.13 to 1 at its maximum in the 2014 general election — by eliminating one Lower House seat each from six prefectures and rejiggering electoral districts elsewhere. It's estimated this would reduce the maximum vote value gap to 1.999 to 1 under the population forecast for 2020.

The implementation of the proposed changes would be a massive operation — not just for the Lower House members elected from affected constituencies, particularly incumbents from Abe's Liberal Democratic Party who face a game of musical chairs with their colleagues — but also voters, who must be fully informed on how their electoral districts will change to eliminate confusion.

However, the proposed changes wouldn't be the end of the story. The electoral reform legislation enacted last year calls for the further redistribution of Lower House seats across constituencies under a mechanism that better reflects the regional population breakdown — as proposed by a panel of experts commissioned by the Lower House speaker — based on data from the next national census in 2020.