Measuring Party-System Dynamics

Well-developed literatures that assess aspects of party-system dynamics in fed­eral systems can guide the development of measures to test hypotheses H1-H3. The independence of first ministers is explored using intra-party linkages and federal electoral data at the regional level.

Canadian parties and the various Canadian party systems have long exhib­ited features that mark them as distinctive. The partisan composition and competitiveness of party systems vary, both between the federal and provin­cial level and from one province to the next. Linkages between parties across jurisdictional boundaries are limited, particularly since the 1970s. A standard comparative work on the relationship between parties in federal systems sug­gests that greater decentralization (as in Canada) is associated with increased incongruence between party systems across the local-national divide, evi­denced in part by internal organizational linkages (Thorlakson 2007; see also Stewart, Sayers and Carty 2015; Gibson and Suarez-Cao 2010) use an index of congruence, attempting to account for both vertical (national-state) and horizontal (state-state) variation. There have also been attempts to synthe­size these various approaches by distinguishing between dynamic (variation in vote share over time), distributional (equality of votes share across units) and party linkage (candidate sharing of party labels), leading to an explosion in ways of studying these effects (Caramani and Kollmann 2017; Schakel and Swendon2018).

Intra-party linkages are used here to explore the independence of first ministers in a manner similar to Thorlakson (2007) and Stewart, Sayers and Carty (2015). This approach is most sensitive to the organizational relation­ship across the federal-provincial divide.

Originally focused on the USA, a now highly comparative literature con­siders the degree of nationalization expressed in the national party system as a means of understanding political coherence, particularly in federations. Nationalization is sometimes thought of as the degree of uniformity of elec­toral swings across elections by district or region. Other conceptions explore the homogeneity of vote distribution by election. Some argue that regional patterns of competition should be excluded altogether (Caramani 2004; Kasuya and Moenius 2008; Lago and Montero 2014; Pruysers 2014). The most widely used approach is the first: that is, the degree to which the vote shares of the major parties do not differ much from one province to the next—that is, regionally (Jones and Mainwaring 2003, p. 140).

We are interested in understanding changes in the disposition of regional voters towards the federal government that might be linked to intergovern­mental relations. Focusing on regional electoral support for the federal gov­ernment across elections provides a second means of thinking about the inde­pendence of first ministers. It draws upon the insights of the nationalization literature but is most sensitive to region- rather than system-wide dynamics. To reduce the complexity of the analysis, the Liberal Party vote share anchors the aggregate analysis of how regional voters view the federal government. The Liberals dominated federal government across the 20th century. As Canada's ‘national party', it is a useful proxy for the role of the national government in executive federalism.

Various measures have been used to explore the degree of one-party or executive dominance of legislatures, with increasing interest in state and pro­vincial dynamics (see Bogaards and Boucek 2010). Vampa (2018) notes that dominance can be conceived of as absolute, relative or as a function of the time a party has been dominant. For simplicity, absolute dominance is mea­sured here as the proportion of total seats won by the largest party. As most provincial and national elections in Canada have used smp electoral systems that over-reward the largest party with a disproportionate share of the seats and control of government, this measure provides a simple test of executive dominance. The next section discusses these correlates of the executive bar­gaining that has reconstituted Canadian federalism.

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