Concurrent Elections and Voting Behaviour: Evidence from an Italian Referendum

Abstract

In September 2020 Italy held a constitutional referendum. On the same election days, many municipalities and some regions held municipal and regional elections. We exploit this unique occasion, caused by the unexpected Covid-19 crisis, to obtain a causal estimate of the effects of the overlap of concurrent elections on the referendum results. When the referendum overlaps with either municipal or regional elections, we find a positive effect on turnout and on the proportion of blank and null votes. We also find a quantitatively small but statistically significant effect on the referendum preferences. We interpret the results through the use of the calculus of voting model, exploiting a slightly modified version of the most widespread one in the literature. Our findings are relevant from a policy-making standpoint, with respect to both fostering turnout and reducing election organizational costs.