THE DPJ AND ITS FACTIONS: BENEFIT OR THREAT?

The Democratic Party of Japanʼs major victory at the 2009 Lower House electionen ded more than half a century of almost uninterrupted rule by the Liberal Democratic Party. Based onformer party a ffiliations, the DPJ is divided into eight factions, each headed by party heavyweights. Since no overall study has yet been done on the DPJ and its internal structure, we still have to ask whether the factions are motivated by ideological concerns or primarily driven by material concerns. The answer to this question has significant effects onthe interpretation of the function of the factions as either integrative or divisive. By using surveys on policy positions of party members that were jointly conducted by the University of Tokyo and the newspaper Asahi shinbun, I asked for the policy diversificationwithinthe party an d the factions. I found evidence that the policy diversificationwithinthe DPJ is wider thanwithin other parties and that the factions are not mainly based on different policy positions. Therefore we have to reject the assertionthat faction alism withinthe DPJ is primarily about policies. We also have to reject the assumption that the factions may act as an integrative mechanism within the party. We rather suggest that they are based on material (self-)interests. In the same manner as the LDP factions, the factions of the DPJ may become "parties within the party", posing a major threat to the unity of the party if factionalism within the DPJ is intensifying.