A Tournament Theory of Pork Barrel Politics: The Case of Japan

How do politicians motivate voters to turn out and support them? We posit that incumbents construct tournaments between groups and distribute rewards to groups based on the levels of electoral support provided. We test our propositions in Japan, where incumbents can discern relative levels of support provided by municipalities in their districts and influence spending in ways that reward certain municipalities over others. Using new data on approximately 3,300+ Japanese municipalities in 1980 to 2000, we show that when municipalities are ranked according to their levels of support for Liberal Democratic Party winners in their district, those at higher ranks get larger rewards, the difference in size of the reward increases at higher ranks, and those in districts where municipalities vary more in size also receive larger rewards. Our findings support the theory and help explain other features of Japanese politics, including why pork tends to flow to relatively unsupportive districts.