Regarding the analysis of European economic policy choices since 2010, the literature has largely taken the path of intergovernmentalism, concluding that the member states were the key leaders of the economic and fiscal negotiations and relegating the Commission to the loser status. This article aims to open the black box of European economic policy-making through process tracing and embed a discussion on policy entrepreneurship by the Commission within an analysis of policy change in economic governance. Using theory-testing process tracing and developing a causal mechanism grounded in Kingdon’ s multiple stream framework (MSF) (Schimmelfennig 2014 ), this article argues that a high level of systemic ambiguity and an individual logic of political manipulation are necessary for policy entrepreneurs to successfully open windows of opportunity and couple the streams leading to supranational delegation. To support our argument, we rely on a series of semi-structured interviews conducted between June and July 2015 in the Commission, the European Parliament (EP), the Council of the European Union (EU) and the European Central Bank (ECB), as well as newspaper articles, the unfolding literature and policy document analysis. The first section of this article will specify the causal mechanism through which a crisis of implementation contributed to supranational delegation (Beach and Brun Pedersen 2013 ). This causal mechanism will test the role of DG ECFIN as a bottom– up entrepreneur. Using comparative analysis between the 2005 and the 2011 SGP reforms, the following two sections look at the intermediate steps necessary to identify the causal process for the 2005 and 2011 SGP reforms.
