Coalition Governments and Political Instability under Premier-Presidential Systems: Comparing Bulgaria and Romania

Author : Tsai Jung Hsiang

Abstract : While aggregate comparative scholarship suggests that premier-presidentialism yields superior democratic quality and governance effectiveness compared to president-parliamentarism, this binary classification risks an ecological fallacy by masking significant individual variations in performance. This paper examines why premier-presidential systems, when combined with fragmented multiparty systems, function as structurally volatile institutional arrangements. Focusing on Bulgaria and Romania as deviant Eastern European cases from 2002 to 2026, we analyze how domestic variables—such as political polarization, intra-party factionalism, and ideological heterogeneity—generate chronic political instability. We develop two distinct operational models: a fragmented governance model under a constitutionally constrained president (Bulgaria) and a polarized governance model characterized by intense dual democratic legitimacy conflicts during cohabitation (Romania). The comparative analysis reveals that the electoral system of proportional representation routinely yields fragile, ideologically incompatible coalitions prone to early collapse. Furthermore, semi-presidential executives rarely remain neutral arbiters; instead, they actively leverage constitutional and informal resources to shape cabinets, which frequently accelerates legislative deadlock. The findings demonstrate that premier-presidentialism’s institutional advantages do not insulate a state from severe governance crises when combined with an unstructured party system and active presidential intervention, emphasizing that constitutional design must always be evaluated alongside party system characteristics and actor behavior.

Keywords : Semi-presidentialism, Premier-presidentialism, Coalition Governance, Political Instability, Bulgaria, Romania.

Conference Name : International Conference on Political Risk and Global Security (ICPRGS-26)

Conference Place : Ho Chi Minh City, Vietnam

Conference Date : 11th Jul 2026