Unequal Geographic Representation in a Mixed-Member Electoral System: Evidence from the German Bundestag

Abstract

This paper demonstrates a systematic geographic bias in the German mixed-member electoral system. This bias concerns the composition of the individual party groups, and, by extension, the composition of the parliament: The Bundestag is much more urban than it would be under equal geographic representation. The bias is caused by the distribution of list seats across districts: since parties have incentives to give the best list positions to candidates from their strongest districts, regions where the vote is more fragmented systematically get more representatives. Since the vote is more fragmented in urban districts, these districts have more MPs than rural districts. The paper empirically analyses Bundestag elections between 1994 and 2017 and demonstrates that geographic disproportionality has increased strongly with the growing fragmentation of the German party system. This affects substantive representation in terms of leadership positions and voting behaviour in the Bundestag. Unequal representation in the German political system therefore also has a geographic component.