Japanese political parties debate House of Representatives seat reductions

Japanese political parties are negotiating proposed reforms to the House of Representatives electoral system, specifically regarding the reduction of seats. The Liberal Democratic Party (LDP) has proposed reducing the number of proportional representation seats by 31, a move based on projected population declines. LDP Diet Affairs Committee Chair Murai expressed strong interest in passing the reform bill during the current Diet session.

The Democratic Party for the People has countered the LDP proposal, suggesting a reduction of only 19 seats instead. They argued that calculations should be based on confirmed 2025 population data rather than 2030 projections.

Other proposed changes include switching the proportional representation seat allocation method from the D'Hondt method to a modified Sainte-Laguë method, which may make it easier for smaller parties to gain seats. Additionally, there is a proposal to raise the minimum vote threshold required for candidates to win a seat through proportional representation from one-tenth to one-sixth of valid votes. While some parties have expressed openness to these technical changes, others have voiced opposition to leaving seats vacant if a party lacks sufficient candidates.