Dynamics of inter-party and intra-party coalition building: a nested-game interpretation of legislator defection from a dominant political party in Japan

Abstract

Under what conditions do legislators defect from a dominant political party? We ask this question with a focus on the case of Japan’s Liberal Democratic Party (LDP) split in 1993. Based on a nested-game model, which depicts factions engaging in intra-party and inter-party coalition building simultaneously in two arenas, we argue that the anti-mainstream faction defected because it was marginalized and had little chance of being powerful within the LDP while the possible change in the electoral system and the success of a new conservative party enhanced its expectations of gaining power within the Diet. Show more