Does the Electoral Rule Matter for Political Polarization? The Case of Brazilian Legislative Chambers

Abstract

This study explores the effects of electoral rules on political polarization in the legislative branch of government.Since in Brazil the districts are also the states, and senators are chosen according to the plurality-majority rule while representatives are determined by a proportional rule, the comparison between legislative chambers enables one to test whether the plurality-majority rule induces politicians to behave less moderately, and whether the proportional rule has the opposite effect. To estimate these effects, roll call data from 1988 to 2010 was analyzed and legislators' ideal points were estimated using WNOMINATE. Evidence in favor of the hypothesis was found, although not in every circumstance.Keywords: Polarization; electoral rules; roll call vote; Wnominate.* http://dx.doi.org/10.1590/1981-38212014000200012 For replication, see bpsr.org.br/files/arquivos/Dataset_Bernabel.html I thank Becky Morton, Howard Rosenthal, Gabriel Cepaluni, Manoel Galdino, Amâncio Jorge de Oliveira, and BPSR's three anonymous reviewers for helpful comments. I also thank Fernando Limongi, Danilo Medeiros, and the Centro Brasileiro de Análise e Planejamento for generously sharing the database for this study. Last but not least, I thank Umberto Mignozzetti for sharing the R code to convert the data into a format suited to run the WNOMINATE function. All remaining flaws are my own.

Formal Comparisons of Legislative Institutions: Ideal Points from Brazilian Legislatures

“…Greater standard deviations translate to less cohesion, as the ideal points of the individuals in the party are more spread out in this case. The results are that there is exactly one instance of a party more cohesive in the Senate than the Chamber -the PFL in the 52 nd legislature, supporting Desposato's (2006) findings and contrary to those of Bernabel (2015). These results are shown in Table 02.…”

“…Our second hypothesis is therefore H2: there is a significant difference in party voting behavior across houses, in particular the PMDB, which is operationalized in the same way as H1. Desposato (2006) and Bernabel (2015) also disagreed on party cohesion within these legislatures, with the former finding more cohesion in the Chamber and the latter finding the opposite. This suggests H3: parties in the In order to test these hypotheses, I utilize methods detailed in Kruschke Were the differences zero in any legislature, we would see that some part of any one of the histograms touches zero.…”

“…To productively compare these houses, we must place both on a common scale, as noted by Bernabel (2015). In order to do so, we must know which proposals were voted on in both houses, and on which versions of the proposals the houses voted, and which are common to both houses.…”

“…Hence hypothesis 02 receives support for all major parties except the PMDB. The 'extremity' argument of Bernabel (2015), that senators within each party vote more for the party than deputies of the same party, is the inverse of Desposato's (2006) claim that the parties in the Senate are less cohesive. One way to examine these arguments is to analyze the standard deviations of the t-test for a difference between the party means of both houses.…”

Avaliando vínculos entre partidos e deputados nas Assembleias Legislativas brasileiras

“…Quando se trata o espaço da competição política de forma multidimensional, a clivagem liberal (progressista) / conservador aparece como uma das dimensões a serem consideradas (Sartori, 2005;Tarouco e Madeira, 2013;Bernabel, 2013 Brasil, a relevância dos partidos e o grau de competitividade do sistema político ainda encontram-se vinculados ao tamanho dos municípios, embora o mesmo não possa ser dito a respeito da tese segundo a qual "partidos conservadores predominariam em municípios rurais, enquanto partidos de centro e esquerda prevaleceriam nos centros mais urbanos" (Marenco dos Santos, 2013, p. 18). Em outras palavras, seria razoável esperar que naqueles contextos mais tradicionais, ou conservadores no sentido "clássico" do termo, prevalecessem as relações de tipo personalista, ou familiares, na política, em vez da mediação dos partidos.…”