Determinants of invalid voting in Latin America

Although elections in Latin America are often characterized by very high levels of blank and spoiled ballots, there has been little if any systematic research into the phenomenon. Previous research from Europe, the U.S., and Australia has usually seen invalid voting as deriving from socio-demographic factors (literacy, education, wealth), institutional factors (electoral system and ballot structure), and political factors (alienation and protest). We operationalize these models for Latin America, using a cross-sectional time series data set including 80 legislative elections held in 18 democracies between 1980 and 2000. Socioeconomic variables such as urbanization and income inequality are associated with levels of invalid voting, while institutional variables such as compulsory voting, electoral disproportionality, and the combination of high district magnitude and a personalized voting system tend to increase blank and spoiled ballots. Moreover, regime-level factors such as political violence and the level and direction of democratic change also shape the rates of invalid voting.