The Psychological Impact of Electoral Laws: Measuring Duverger's Elusive Factor

Abstract

Duverger's law regarding the impact of electoral systems on party competition depends upon two effects: the mechanical and the psychological. The former is well defined and well documented, whereas the latter has more often been a matter for theoretical speculation. In this article we provide an operational definition of the psychological effect of electoral systems and measure its impact across twenty democratic systems over more than a century. Our findings suggest that it does exist, that it works as Duverger predicted and that its impact is about the same magnitude as the mechanical effect.

What Explains Voter Turnout in Latin America?: A Test of the Effect of Citizens' Attitudes Towards the Electoral Process

“…Studies have, for the most part, confirmed the hypothesis that countries with a higher number of competitive districts have higher overall rates of turnout as a result of mobilization efforts by parties (Jackman 1987;Blais and Carty 1991;Jackman and Miller 1995;Radcliff and Davis 2000). In addition, PR should have a positive effect on turnout due to the disproportional effects in the translation of votes into seats in majority-type electoral systems, which could diminish voters' sense of political efficacy, increasing the belief that their vote is of no importance and leading them to abstain from voting (Blais and Dobrzynska 1998).…”

“…Institutional and political context explanations focus on the effects of electoral rules and the structure of the political system on voters' decision-making calculations about whether to vote. The electoral system (Blais and Carty 1991;Radcliff and Davis 2000), the electoral cycle (Fornos et al 2004;Dettrey and Schwindt-Bayer 2009), compulsory voting laws (Jackman 1987;Hirczy 1994;Jackman and Miller 1995;Pérez-Liñán 2001;Fornos et al 2004;Power and Garand 2007), unicameralism (Jackman 1987;Pérez-Liñán 2001;Fornos et al 2004;Kostadinova and Power 2007), district magnitude, the disproportionality of the electoral system, nationally competitive districts, and party fragmentation (Jackman 1987;Pérez-Liñán 2001;Fornos et al 2004;;Lehoucq and Wall 2004;Kostadinova and Power 2007) have all been linked to voter turnout.…”

“…On the other hand, PR should have a negative effect on voter turnout due to the higher number of parties that it fosters in comparison to majority systems. Almost all of the empirical research has found a negative correlation between the number of parties and turnout (Jackman 1987;Blais and Carty 1991;Blais and Dobrzynska 1998;Radcliff and Davis 2000), except in Latin America, where there seems to be no relationship between these variables (Pérez-Liñán 2001; Fornos et al 2004). …”

Which Matters Most: Party Strategic Exit or Voter Strategic Voting? A Laboratory Experiment

“…This electoral system is widely used to elect national parliaments throughout the world, especially in commonwealth democracies (Reynolds, Reilly and Ellis 2005). As mentioned above, an abundant literature shows that this electoral system tends to reduce party system fragmentation (Blais and Carty 1991;Lijphart 1994;Powell 2000;Taagepera and Shugart 1989).…”

“…They demonstrate that proportional representation rules produce a high number of parties whereas this number is much lower under the plurality rule (Blais and Carty 1991;Lijphart 1994;Powell 2000;Taagepera and Shugart 1989). This effect is so established in the literature that we sometimes give it status of a law: Duverger's law (Duverger 1951).…”