Natural disasters and electoral outcomes

Natural disasters are good examples of catastrophic events that may affect vote decisions. In this study, we analyze how the occurrence of earthquakes changes voters' behavior at municipal elections and which channels drive this change, focusing in particular on the role of media exposure. We exploit data from 13,338 municipal electoral cycles where incumbents seek reelection between 1993 and 2015 in Italy. We apply a difference-in-difference strategy with time and cities fixed effect to the probability of reelection and vote share using three different control groups: the universe of municipalities, a sub-sample of neighboring municipalities, and a sub-sample of municipalities identified by a one-to-one nearest-neighbor propensity score matching procedure. We find that the occurrence of destructive earthquakes significantly increases the incumbent mayors’ chance of being reelected and their vote share. We argue that this result is driven by the incumbent mayor advantage in offering recovery from disaster damages combined with a higher visibility on the media in the aftermath of the disaster. Thus, the mediatic relevance of earthquake occurrence may bias voters towards the incumbent.