Sebastian Juhl

Parties' success on Election Day and their ability to subsequently implement reforms is affected by their ability to convey a cohesive image. Consequently, managing the diverse and, at times, conflicting interests within a party is of vital importance for office-motivated parties. Due to the unprecedentedly high levels of media attention, their national congresses provide a unique opportunity to present their internal coherence and preference convergence to the broad public. Yet, do voters care at all about intra-party politics and do they update their beliefs about parties in light of their behaviors at the national congresses? In order to identify the causal effect of national party congresses on the voters' perceptions of party unity, we develop a deductive-sequential mixed methods research design in which we combine qualitative case studies with a quasi-experimental regression discontinuity design based on individual-level panel data from Germany. We find that disagreement at the congresses negatively affect the voters' perceptions about party unity. The results hold important implications for our understanding of the circumstances that allow parties to suggest and implement reforms.