Unravelling a Trefoil Knot: Comparative Perspectives on Electoral Reform and Party System Change in New Zealand and Britain’s Devolved Parliaments.

Abstract

This thesis is an examination of the relationship between electoral reform and party system change in the context of New Zealand and Britain. It attempts to engage in a qualitative comparative analysis of these two environments, to see what conclusions might be drawn about wider relationships. These countries offer particularly useful comparison because after almost a century of Single Member Plurality elections (‘First Past the Post’), both introduced Alternative Member systems in the 1990s. New Zealand did so for its national elections with the Mixed Member Proportional system (MMP), while Britain did so in Scotland and Wales, with other proportional systems in other ‘second order elections’. Studies of this relationship have long been dominated by an axiom developed by Maurice Duverger, and named after him: Duverger’s Law. This law and hypotheses resulting from it suggest that the electoral system is the strongest determinant of the shape of a given party system. However, this paradigm has come under increasing scepticism. A theoretical exploration of the interaction between electoral reform and party system change reveals that Duverger’s law is no longer an adequate explanation. Rather, a complicated relationship, while empirically and methodologically taxing, is best at explaining resulting outcomes. The ultimate model is one in which electoral reform and party system changes affect each other, with dual lines of causality. Moreover, they in turn are influenced by broader changes in societal makeup and distinct ‘crises’. An in depth analysis of the causes of these change in New Zealand and Britain reveals that such a model is convincing in practice.