Paper short abstract:

Among the electoral systems that form the basis of representative democracy, the electoral districts have been particularly controversial in recent years. In this report, we will identify how changes in electoral district districting have affected Japanese politics and explore future developments.

Paper long abstract:

The electoral system, which is the foundation of representative democracy, has been the subject of much debate in Japan in recent years. These include lowering the voting age, relaxing restrictions on electoral activities, and reexamining electoral administration.

Among these, the electoral district system has become the most controversial issue. As a result of the campaign to correct the disparity in the number of votes and the "unconstitutional state of affairs" ruling by the Supreme Court, a major revision of the electoral districts for the House of Representatives was made in November 2022.

Based on the principle that members of the National Diet are representatives of the people, the current electoral district allocation, which insists on the demarcation of basic municipalities, is questionable. On the other hand, while leaning on the "myth of representation of the people”, the fact remains that regional representatives have been selected. We can find the strong path-dependency, not just the pursuit of reelection possibilities for the representatives.

How then, have Japan's electoral districts been divided and changed? There have been major revisions of the electoral district system in 1889, 1900, 1919, 1925, 1945, 1947, and 1994. We can confirm that amendments, which were extremely frequent in the prewar period, became rare in the postwar period. This is inseparable from the instability of party politics and democracy in the prewar period and its stability in the postwar period. At the same time, it is also the institutional basis for the high probability of regime change in the prewar period and the establishment of one-party rule in the postwar period. Japan's electoral district system can be said to be a spatial political system that has strongly defined Japanese politics in the prewar and postwar periods.

In other words, understanding the effect of electoral districts reform is a major aid to understanding Japan's political culture and climate. In this report, we focus on the continuum of the electoral districts in order to examine their influence on Japanese politics.