Canadian Journal of Political Science

Research Article

Polarized Pluralism in the Canadian Party System: Presidential Address to the Canadian Political Science Association, June 5, 2008

Richard Johnstona1 c1

a1 University of Pennsylvania


Abstract. The Canadian party system is an example “polarized pluralism,” whose key feature is domination by a party of the centre. Centrist domination induces centrifugal tendencies elsewhere in the system. Polarized pluralism accounts for several of the system's peculiar features: three-party competition in individual ridings, contrary to the predictions of Duverger's Law; the existence and episodic dynamics of sectional parties; boom and bust cycles in Conservative party electoral history; and the large gaps between federal and provincial outcomes within many provinces. But domination by a centrist party itself demands explanation.

Résumé. Le système canadien des partis politiques exemplifie le «pluralisme polarisé», dont l'élément clé est la force dominante d'un parti du centre. Une telle domination induit des tendances centrifuges ailleurs dans le système. Pour sa part, le pluralisme polarisé explique plusieurs éléments du système canadien : la présence de trois partis compétitifs au niveau de la circonscription, malgré les prédictions du Duverger; l'existence même et la dynamique des partis sectionalistes; l'alternance entre force et faiblesse dans l'histoire du Parti conservateur; et les grands écarts qui se présentent dans plusieurs provinces entre les élections fédérales et les élections provinciales. Dans ce contexte, la force d'un parti centriste se doit d'être expliquée.


c1 Richard Johnston, University of Pennsylvania, 208 S. 37th Street, Room 206, Philadelphia PA,19104-6215,


Acknowledgments: Many colleagues have contributed to this address, often without knowing it, but special mention must be made of Amanda Bittner and Scott Matthews. Thanks to the University of Pennsylvania for material support. Data from the 2004 and the 2006 Canadian Election Surveys were provided by the Institute for Social Research, York University. The surveys were funded by Elections Canada and the Social Sciences and Humanities Research Council of Canada. Co-investigators were André Blais, Joanna Everitt, Patrick Fournier, Elisabeth Gidengil, and Neil Nevitte. None of these persons or institutions is responsible for the analyses and interpretations presented here. I wish to dedicate the address to the memory of Bill Irvine.