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This page lists the project publications as well as selected other publications making use of the EUPLEX dataset.

Project publications

Hurka, S. and Steinebach, Y. (2020) Legal Instrument Choice in the European Union. Journal of Common Market Studies.
doi: 10.1111/jcms.13068 PDF

Abstract: Regulations and directives are the central legal instruments used by the EU. In some instances, the Commission is not legally required to choose a specific legal instrument, but can make this decision autonomously. However, we know surprisingly little about the factors that influence this decision. Based on an original dataset of all directives and regulations proposed by the European Commission in ordinary legislative procedures between 2009 and 2018, we find that the choice of a legal instrument is strongly determined by prior policy decisions and varies systematically across policy areas depending on the extent to which they have traditionally been addressed under the co‐decision procedure. In addition, we find that the Commission's use of regulations increases under conditions of increased euroscepticism, indicating that instead of granting dissenting member states more room to manoeuvre, the Commission prefers to keep them on a short leash.

Hurka, S. and Haag, M. (2020) Policy complexity and legislative duration in the European Union. European Union Politics, 21(1), 87–108.
doi: 10.1177/1465116519859431 PDFReplication materialLSE EUROPP article

Abstract: This article investigates the impact of policy complexity on the duration of legislative negotiations in the European Union employing survival analysis. We conceptualize policy complexity as a three-dimensional construct encompassing structural, linguistic and relational components. Building on this conceptual framework, we measure the complexity of 889 Commission proposals published under the ordinary legislative procedure between 2009 and 2018. Controlling for institutional and political drivers of legislative duration identified by previous studies, we show that different types of policy complexity influence the duration of the decision-making process in the European Union to varying degrees, at different points in time and partially in unexpected ways. On a general level, our study highlights that developing a better understanding of the origins and consequences of policy complexity in the European Union is a key task for scholars of European integration.

Working papers

Hurka, S. and Haag, M. (2020) The evolution of policy complexity in the European Union. Paper presented at EPSA 10th Annual (virtual) Conference.
Presentation slides

Abstract: Although policy complexity has been identified as one of the major challenges for the European Union (EU) both by practitioners and EU scholars, the complexity of EU legislation is rarely measured and studied systematically. In this paper, we trace the complexity of policy proposals published by the European Commission under the co-decision and the consultation procedures since the Maastricht Treaty. We investigate how policy complexity has evolved over time and assess the extent to which this complexity is affected by the increasing involvement of the European Parliament in the decision-making process and the legal instrument used by the Commission. We analyze several indicators of policy complexity, covering structural, linguistic and legal aspects. The analysis is currently based on more than 4,000 legislative proposals. We find that (a) policy complexity has clearly been on the rise in the EU while the growth rate has slowed down more recently, that (b) the Commission adopts significantly more complex policy proposals under co-decision than under consultation and that (c) the conventional wisdom that regulations carry more complex policy content than directives should be re-considered. The paper thus contributes to a better understanding of how political institutions shape the complexity of policy content in the EU.