Replication Data for Trade and the Politics of Electoral Reform

While recent research on the origins of proportional representation (PR) in Europe
has focused on domestic political explanations, we bring international trade back as an
economic explanation for the politics of electoral system choice. Spurred by Rogowski’s (1987) theory of the trade origins of PR and the political economy literature on trade policy, we argue that political conflict over trade shaped the struggle over electoral reform during the first globalization. Because tariffs were a central and contested issue, economic interests hurt by rising tariffs under the old electoral system have economic motives to support the introduction of PR. To conduct a missing test of the theory, we leverage district level popular votes in Switzerland using a within-country research design. We find support for the core mechanism of the trade theory: demand for protectionism entailed stronger opposition to the introduction of PR. Using panel data, we demonstrate that changes in the relative size of the agricultural sector, the central pillar of support for protectionism, were closely related to changes in support for PR. We also examine legislative voting in Germany, and find that protectionism was linked to subsequent opposition to electoral reform. Altogether, our analysis highlights the relatively overlooked importance of trade in conflict over electoral institutions.