Electoral Volatility in Latin America
Authors: Carreras Miguel , Acácio Igor 
Published: August 2019

Latin American political systems experience significant levels of institutional uncertainty and unpredictability. One of the main dimensions of this institutional and political instability is the high level of electoral volatility in the region. In the last 30 years, traditional parties that had competed successfully for several decades abruptly collapsed or weakened considerably in a number of Latin American countries. New parties (or electoral movements) and political outsiders have attracted considerable electoral support in several national and subnational elections in the region. Even when the main partisan actors remain the same from one election to the next, it is not uncommon to observe large vote swings from one established party to another.

While some scholars and observers expected that the instability in electoral outcomes would decline as democracies aged and consolidated, electoral volatility has remained high in recent decades in many Latin American countries. However, in other Third Wave Latin American democracies (e.g., Chile, Costa Rica, Honduras, and Uruguay), the patterns of interparty competition have been much more stable, which suggests we should avoid blanked generalizations about the level of party system institutionalization and volatility in the region. Cross-national variation in the stability of electoral outcomes has also motivated interesting scholarly work analyzing the causes and the consequences of high volatility in Latin American democracies.

One of the major findings of this literature is that different forms of institutional discontinuity, such as the adoption of a new constitution, a significant enfranchisement, electoral system reforms, and irregular changes in the legislative branch (e.g., a dissolution of Congress) or in the executive branch (e.g., a presidential interruption), can result in higher volatility. Another major determinant of instability in electoral outcomes is the crisis of democratic representation experienced by several Latin American countries. When citizens are disenchanted with the poor performance and moral failures (e.g., corruption) of established political parties, they are more likely to support new parties or populist outsiders.

Weak party system institutionalization and high electoral volatility have serious consequences for democratic governability. Institutionalized party systems with low electoral volatility promote consensus-building and more moderate policies because political parties are concerned about their long-term reputation and constrain the decisions of political leaders. In contrast, party systems with high volatility can lead to the rise of outsider presidents that have more radical policy preferences and are not constrained by strongly organized parties. Electoral volatility also undermines democratic representation. First, the fluidity of the party system complicates the task of voters when they want to hold the members of the incumbent party accountable for bad performance. Second, high instability in the patterns of interparty competition hinders citizens’ ability to navigate programmatic politics. Finally, electoral volatility augments the cognitive load required to vote and foments voter frustration, which can lead to higher rates of invalid voting.