Turning out but not voting: invalid ballots in post-communist parliamentary elections

Large numbers of invalid votes in elections can present a threat to the legitimacy of democratic systems. Focusing on the post-communist countries of Central and Eastern Europe, three theoretical models explaining the incidence of invalid votes are tested using aggregated data from all legislative elections. While the protest behavior powerfully shapes the incidence of invalid votes in less democratic countries, complex electoral systems and concurrent elections are also associated with high levels of invalid voting (indicating voters' error). Conversely, we find that most socioeconomic variables are weak predictors of invalid voting while controlling for institutional and political variables in the region. The study has policy implications that the simple electoral design should be preferred.