Reconciling Parliamentary Size with Personalised Proportional Representation? Frontiers of Electoral Reform for the German Bundestag

Abstract

In the 2017 Bundestag election, the recently reformed mixed-member proportional system (MMP) produced an enlarged parliament with 111 additional seats. As could happen in the future, the Bundestag may even increase in size, so the parliamentary parties committed themselves to a renewed reform in order to curb seat enlargements. This was nonetheless to be done without major changes of the existing MMP. The article analyses the frontiers of such “minimally invasive” reform. Each modification of “personalised PR” that reliably maintains the Bundestag size would compromise one or other of its fundamental features: personalisation or proportionality. We illustrate this by exploring the effects of various single-member district (SMD) reforms that are widely considered the “least harmful” minimally invasive approach. Comprehensive simulations based on survey data demonstrate that the SMD share would have to decrease substantially for maintaining parliamentary size as reliably as two-member districts would do. Thus, any SMD reform would either substantially affect the MMP’s conventional personalisation or curb seat enlargement less effectively.