Overview of the Book
To answer the question of which factors may lead to united or divergent voting behavior of ministers in the Council and MEPs of the same national party, the present study relies on considerations based on rational choice institutionalism and principal-agent theory. Thereby, it is assumed that unity in voting behavior of a national party’s representatives in the EU is mainly affected by the strength of the linkage between the national party and the representatives (e.g. the amount and effectiveness of control mechanisms that national parties employ as principals of both ministers and MEPs) and by the institutional constraints within the Council (e.g. the so-called “culture of consensus” that prevents ministers from voting “No” if they do not have highly convincing objections), as well as institutional constraints within the EP (e.g. the important role of transnational groups in shaping the voting behavior of MEPs).
A mixed-methods approach combining both quantitative and qualitative evidence (cf. Lieberman 2005) is employed. For the qualitative part, explorative interviews with MEPs and Council officials (including former ministers) were performed to explore the linkage mechanisms between national parties and their representatives in the EU and the intra- and inter-institutional decision-making processes in the EU. On the one hand, the qualitative interviews are used as a starting point and motivation for the quantitative analysis; on the other hand, they complement and refine the quantitative findings in order to gain deeper insight into the topic and to add more meaning to the bare figures. For the quantitative part, a dataset merging the voting records (for the same proposals) of Council members with the voting records of MEPs of all governmental parties from the EU-15 member states was compiled, covering recorded votes on Codecision legislation within the period from 1999 to 2009. Descriptive statistics will reveal how often ministers and MEPs of the same national party vote the same way. Furthermore, the effects of different factors related to party affiliation and institutional constraints on voting unity will be estimated using logistic regression models. This approach allows for drawing conclusions on the role of national parties in bicameral EU decision-making based on the observed voting behavior and the qualitative interviews.
The book is structured as follows: The next chapter describes voting in the EU decision-making procedures in detail. Hereby, not only the potential pitfalls but also the strengths of the data will be discussed. Thereafter, the research questions are answered one after the other. In Chap. 3, potential strategies used by national parties for influencing voting behavior in the Council and the EP will be deduced from principal-agent theory. Interview data as well as survey data is used to analyze how national parties control and coordinate their ministers and MEPs. Chapter 4 sets out to answer the question of how “institutional constraints” shape the voting behavior of MEPs and ministers. Findings from previous quantitative empirical studies will be tested for validity. Furthermore, the quantitative findings will be complemented with qualitative evidence from interviews. While Chaps. 3 and 4 are mainly used to recapitulate and test previously gathered knowledge in order to describe the factors (i.e. the independent variables) that may affect voting unity between ministers and MEPs (the dependent variable), in Chap. 5, unchartered territory is entered and “Voting Unity” itself is studied. After providing some descriptive statistics, the effects of the independent variables on “Voting Unity” are estimated. Chapter 6 tries to disentangle the different factors that affect voting unity and investigates whether national parties are able to ensure cohesive voting behavior of their ministers and MEPs despite divergent institutional constraints. Finally, the conclusion sets out to explain the empirical findings and summarizes what has been learned about national parties and bicameral decision-making in the EU.