Party government in Europe? Parliamentary and semi-presidential democracies compared PETRA SCHLEITER & EDWARD MORGAN-JONES Department of Politics and International Relations, University of Oxford, UK Abstract. Control over government portfolios is the key to power over policy and patron- age, and it is commonly understood to lie with parties in European democracies. However, since the democratic transitions of the 1990s, Europe has had nearly equal numbers of parliamentary and semi-presidential regimes, and there is evidence that the ability of parties to control government posts in these two regime types differs.As yet, political scientists have a limited understanding of the scale and causes of these differences. In this article a principal- agent theoretical explanation is proposed. Data are examined on 28 parliamentary and semi-presidential democracies in Europe that shows that differences in party control over government portfolios cannot be understood without reference to the underlying principal- agent relationships between voters, elected politicians and governments that characterise Europe’s semi-presidential and parliamentary regimes. Comparative work on European governments over the last fifty years has regarded government composition as determined by parties. Although schol- ars have variously stressed the importance of a party’s legislative seat share (Gamson 1961; Warwick & Druckman 2006), bargaining power (Schofield & Laver 1985) and formateur status (Baron & Ferejohn 1989) in shaping the share of government portfolios that a party holds, the basic assumption under- lying this literature is that parties control government posts (Budge & Keman 1990; Klingemann et al. 1992; Laver & Budge 1992; Laver & Shepsle 1994). This assumption is driven and justified by the literature’s focus on the regime type that dominated amongst European democracies for most of the twentieth century: parliamentarism. Yet, the democratic transitions of the 1990s in East and Central Europe and the former Soviet Union have fundamentally altered the continent’s constitu- tional traditions (Amorim Neto & Strøm 2006). Today Europe embraces nearly equal numbers of parliamentary and semi-presidential democracies, and there is evidence to suggest that parties are not equally dominant actors in these two regime types. The case-oriented literature on governments in Europe’s semi-presidential regimes documents the appointment and dismissal of ministers, prime-ministers and even entire governments by popularly elected presidents, which often reduces party control over government posts. European Journal of Political Research 48: 665–693, 2009 665 doi: 10.1111/j.1475-6765.2009.00847.x © 2009 The Author(s) Journal compilation © 2009 (European Consortium for Political Research) Published by Blackwell Publishing Ltd., 9600 Garsington Road, Oxford, OX4 2DQ, UK and 350 Main Street, Malden, MA 02148, USA