Electoral regime and trade policy

We study how trade protection varies with the electoral rules for legislative representation. In particular, we investigate different hypotheses about why trade policy differs between countries with legislatures elected by a plurality election rule in single member constituencies and legislatures elected by a proportional, or party-list, rule. Our results, which are in line with the existing literature, show that countries with list-PR systems tend to have lower trade barriers than countries with majoritarian systems. We expand on this literature by looking at the mechanisms through which this correlation can be explained. Our findings indicate that, contrary to existing theory, neither constituency size nor party strength are important when explaining this correlation. Country size does matter, but does not explain the whole of the correlation.