Redistricting in Japan: Lessons for the United States

Abstract

Japan is regularly criticized for the malapportionment of its election districts. In contrast, the United States has problems with gerrymandered election districts, even though district boundaries are crafted with meticulous attention paid to population equality among its districts. Japanese redistricting practices prevent gerrymandering of district boundaries, but at a cost of tolerating higher levels of malapportionment than would be allowed in the United States. I analyze the effects of Japan's redistricting rules and find that they have effectively prevented any malapportionment or gerrymandering that benefits a specific political party. I also show that in terms of actual votes cast, the Japanese system produces greater equality between districts than the results obtained in the United States, suggesting that US redistricting practices could be improved by modeling them after the Japanese example.