Diet members discussing electoral reforms need to correct the huge disparity in vote value between constituencies in time for the next national elections to be held by 2016. Lawmakers should also set their sights on an overhaul of the electoral systems for the Diet's two houses and explore what kinds of systems would be appropriate for the different roles of the two chambers under the nation's bicameral system.

Electoral reforms are a sensitive issue for lawmakers that affect their chances of winning Diet seats, and political parties rarely agree on such matters because their very partisan interests are at stake. The ruling coalition and several opposition parties have recently agreed to set up a third-party panel of experts to discuss Lower House electoral reforms, after the parties themselves failed to narrow their differences.

The Liberal Democratic Party-led alliance calls for reducing proportional representation seats, while the Democratic Party of Japan and other opposition forces say seats should be cut from electoral districts with less population and added to more populous constituencies, thereby narrowing vote-value disparity.