Duverger's Law

Blog 7: Duverger’s Law

            In Brazil, the electoral system is mixed: the president is elected via majority vote, while the National Congress is elected by proportional representation. Brazil has a multiparty system, one with so many parties that no one party can gain power alone, but instead they form coalitions (IPU).

            The Chamber of Deputies is elected using the party-list form of proportional representation known as the “open list”. In this system, the voters are given a list of parties, which they choose from, and then within the list of parties they are allowed to choose the candidates that will receive seats in the Chamber if the party wins (Wikipedia). 513 seats are up for grabs in the Chamber. This is opposed to the closed list system in which the candidates are chosen by the party leaders and not the voters at large. However, in the Federal Senate, senators are elected with a plurality, in the first-past-the-post manner, meaning, whoever has the most votes in the state gets the seats. This system is not proportional. In the Federal Senate, senators are elected for eight-year terms, and there are three senate seats per state and for the federal district.  

            Given the mixture of electoral systems in the Brazilian government and Duverger’s Law which claims that the effective number of parties in any electoral system is a function of the electoral rules (Samuels), one could predict that the state could be either two effective party system, as would be produced by SMDP, or a multi-party system, seeing as there is a great deal of proportional representation in the country. In the Presidential election, though following the primaries, there were as many as three parties that received at least nineteen percent of the votes, and that was in the majority rules presidential election. According to the number of effective parties equation we were given in class, the number of effective parties within Brazil is around 6, and to top this off there are 22 parties that hold seats in the Chamber of Deputies. That is an enormous number of parties in one country, but it is produced by the nature o the system. Not only is there proportional representation allowing large numbers of parties into the Chamber of Deputies, but this also gives such parties credibility in other areas of governments. Along with this, Brazil’s parties, in order to gain any semblance of power, band together in coalitions so that parties with similar ideas tend to win the vote.

            Looking at these results, I would argue that Brazil does follow Duverger’s Law, in that the number of effective parties does reflect the electoral rules—there are 22 parties with seats in Congress (PR) and 2 coalitions with a notable amount of power (SMDP). SO due to the mixed nature of the system, we find that Brazil has a mixed amount of effective parties/coalitions