Duverger's Law is Working in Italy

In 1993, Italy adopted an electoral system based largely on single-member districts (SMD) based, at least in part, on the hope that SMDs would lead to a two-party system and alternation in government. That idea is known in political science as Duverger's law. The overwhelming consensus among specialists in Italian politics would appear to be that Duverger's law is not working very well in Italy. I will argue, to the contrary, that Duverger's law is working exactly as should have been expected. Although one may see little evidence of movement toward a two-party system at the national level, between the 1994 and 1996 elections, more than 80% of electoral districts moved closer to bipolar competition between two candidates. A dynamic analysis of electoral districts confirms the powerful operation of Duverger's law in Italy.