How can we explain variation in parliamentary adaptation to European integration? On first sight, the creation and diversity of EU-related oversight institutions in the parliaments of the member states appears puzzling. The conventional view is that parliamentary majorities, which have the votes to create the institutions they need for their policy and electoral goals, lack interest in formal parliamentary rights and capacities. They prefer to work with party leaders in government through party channels. Opposition parties that are typically credited with a demand for all formal rights and opportunities that they can get in order to influence government policy, or replace it at the next election, lack the votes to push through adaptation to the EU against the will of the majority. The literature has predominantly focused on the context of parliamentary politics, notably existing rights of parliaments in domestic politics and popular Euroscepticism. Both factors can plausibly be expected to shape variable responses of parliamentary actors to integration. Yet, the arguments advanced in their support do not specify how or why the aforementioned conundrum between government and opposition parties can be resolved.
Selected studies have argued that it may well be true that the parliamentary majority is not normally interested in formal oversight institutions. However, this changes under specific conditions, notably the existence of coalitions that are difficult to manage and minority government. Coalitions with heterogeneous policy preferences have to solve problems of joint policy-making (Martin and Vanberg 2011). Legislative institutions might help insofar as they allow bringing parliamentarians into coalition parties' in efforts to monitor each other. Under a minority government, legislative institutions could be a way to deal with the mismatch of the legislative and the office coalition. They could help parties represented in the former but not in the latter to secure their policy influence. There are various problems with both views. Primarily, however, the issue is that they understand EU-related oversight institutions as solutions to problems that they do not really solve. The first priority of party leaders confronted with challenges of coalition or minority governance will be to solve these problems within the institutions that are available. Indeed, the emergence of minority government may be much more a result of, than an explanation for, particular parliamentary institutions (Strom 1990). Even if parties consider institutional reform, they are unlikely to create European Affairs committees because coalition partners disagree over taxation or environmental policy. They would first aim for reforms of parliamentary rights in domestic policy-making, where the electorally most important decisions are still taken.
This chapter instead suggests that the nature and configuration of the constitutional preferences of parties in the member states' parliaments explain institutional adaptation to EU affairs. Parties do not merely regard institutions as means to their policy and electoral ends. On the contrary, they have deeply rooted, systematic views on the desirable political order of the EU (e.g. Jachtenfuchs etal. 1998; Marcussen etal. 1999; Schmidt 2006). Parties' constitutional preferences are rooted in their ideology. They are also closely related to democratic norms and existing institutions, both of which reflect constitutional preferences that have become consensual among European and national policy-makers. Views of what institutions the EU should have vary between parties and member states as well as within parties. However, the national context shapes and constrains the range of constitutional preferences parties adopt and, therefore, produces a situation in which the most pronounced variation lies between groups of parties from different countries. What is more, intra-party diversity encourages party leaders to look for inclusive parliamentary positions that avoid creating electorally damaging intraparty divides.
Against this background, the patterns of parliamentary adaptation to European integration depend on the constitutional preferences prevailing among parliamentary parties of different member states (cf. Rittberger 2005; Winzen etal. 2015). Parties evaluate steps to deepen European integration in light of their constitutional preferences, democratic norms, and domestic institutions. To the extent that European integration undermines the institutional authority of national parliaments, parties perceive democratic deficits and demand reforms that anchor the exercise of public authority at the European level in democratic procedures, including parliamentary competences. In some member states, parties predominantly tend towards federal constitutional preferences and regard the creation and empowerment of the EP as the right solution to parliamentary deficits. In others, intergovernmental views and support for national parliamentary authority prevails. Additionally, some countries, in contrast to others, have traditions of strong parliamentary rights and capacities in the domestic policy process. Where opposition to the EP and support for national parliaments prevails, and where traditions of strong parliamentarism exist, parliamentary reactions to integration will, therefore, be likely and strong. Where federalist views and weak parliaments are the rule, reactions will be unlikely and weak.
Chapters 4 and 5 test these arguments about variation in parliaments' institutional adaptation to the EU. Subsequently, the argument is extended to the question of why parliaments lack a strong direct role at the European level. Additional complications arise in answering this question. Notably, while domestic reform choices are taken within countries, decisions on the direct role of parliaments will require parties from different countries to come to some agreement on what collective competences they want to have in EU policy-making. What is more, whereas federalist and intergovernmental constitutional preferences entail clear prescriptions for the importance of national parliamentary rights and competences, they are less clear on their direct role outside of the national context. For instance, it would certainly not be in line with intergovernmentalist models of the EU if national parliaments where to operate internationally alongside the governments of their own making. Before we return to these issues, the first task is, however, to test explanations of domestic adaptation to integration.