Electoral volatility and the dynamics of electoral reform

Recent elections in Europe have shown that a context of increasing citizen distrust towards democratic institutions may lead to very high levels of electoral volatility and to the emergence of new parties. On the other hand, institutional reforms are sometimes presented as a solution to citizens’ discontent with political institutions. Focusing on a specific type of political institution ? electoral systems ? the question addressed in this study is whether high levels of electoral volatility may trigger electoral reforms. The article investigates the conditions under which reforms affecting the electoral system’s degree of openness to new parties were enacted in 25 European countries between 1945 and 2012. The findings demonstrate that volatility due to the emergence of new parties is the most powerful explanation to account for the introduction of electoral reforms, particularly those that hinder the entry of new parties into the system.