Endogenous Parties in an Assembly


  • I am grateful to Justin Fox, Sandy Gordon, Dimitri Landa, Jeffrey Lax, Matt Jackson, Andrew Martin, Tom Palfrey, and Keith Poole for their suggestions and their help.

Jon X. Eguia is Assistant Professor of Politics, New York University, 19 West 4th Street, New York, NY 10012 (eguia@nyu.edu).


In this article, I show how members of an assembly form voting blocs strategically to coordinate their votes and affect the policy outcome chosen by the assembly. In a repeated voting game, permanent voting blocs form in equilibrium. These permanent voting blocs act as endogenous political parties that exercise party discipline. In a stylized assembly I prove that the equilibrium parties must be two small polarized voting blocs, one at each side of the ideological divide.