The adoption of proportional representation (with Lucas Leemann), 2014 Journal of Politics. 76(2): 461-478
The debate between economic and political explanations of the adoption of proportional representation has yielded mixed results. We reexamine this debate and argue that one has to take the different levels on which the causal mechanisms are located into account. This leads to a novel reformulation of Rokkan’s hypotheses: we claim that proportional representation is introduced when legislators faced strong district-level competition and when their parties expect to gain seats from a change of the electoral law. In the empirical part, we test these competing predictions using a roll-call analysis of support for the adoption of proportional representation by members of the German Reichstag. We evaluate the relative importance of district-level competition and vulnerability resulting from electoral inroads made by Social Democratic candidates, partisan calculations arising from the disproportionalities in the allocation of votes to seats and economic conditions at the district-level, specifically variation in skill profiles. Support for the adoption of proportional representation is explained by a combination of district vulnerabilities and seat-vote disproportionality.