This special issue looks at the normative implications of EU global regulatory efforts in the area of environmental policy. The EU Environmental Emissions Trading System (EU-ETS) represents an example of successful application of EU environmental standards where global standards harmonization had failed. The intersection between EU law and global law, however, seems increasingly porous and difficult to decipher. Post-Lisbon, the EU increasingly functions like a State in its actions with the world. Nonetheless, the operation of international law internally within the EU legal order has been the subject of many distinctive constitutional periods, both prior to and after the Treaty of Lisbon. In the recent judgment of the Grand Chamber of the Court of Justice on the EU-Emissions Trading System, the Court rejected claims that the application of the EU-ETS scheme to the aviation sector, specifically US airlines, was unlawful under EU and international law. In the realm of the environment, EU environmental protection is both a value and normative aspiration. Yet what is a successful legal outcome of the adoption of ambitious and aggressive global legal regulatory frameworks in this domain? How should contemporary EU global policy and value ambitions be adjudicated in law? The case raises broader issues about the legitimacy of EU law and externalities arising from extended EU competences to positively promote EU constitutional values beyond Europe. While using this case as its starting point, this special issue sets out to look at the wider constitutional questions asked by it.

The EU legal system, with its many hands and complex architecture, in which national and European powers are closely interwoven, requires a particular form of cooperation. This delicately developed cooperation may be influenced by the EU's ambition to take a statelike role in international relations. Indeed, the basic assumption underlying this Article is that it is not only the EU's complexity that influences the EU's external actions—usually seen as limiting the EU's capacity to speak with one voice—but also that the EU's external actions influence its internal set-up and cooperation practices. As a result of the EU's participation in international legal regimes, established organizational principles might come under pressure. Furthermore, within the complexity of the European legal order, the potential consequences could be more disturbing for stability than within the—monolithic, in comparison—structure of states.

European Union law must be interpreted and its scope delimited, to the extent possible, consistent with the relevant rules of international law. Article 3(5) of the Treaty on European Union (TEU) provides that “the EU shall uphold and promote … the strict observance and the development of international law.” A similar legal commitment can be found in the constitutions of most EU Member States, which in some cases is about delegation of powers, whilst in others it concerns the achievement of global objectives. Article 3(5) of the TEU is also reminiscent of the judicial canon laid down by the United States Supreme Court in Charming Betsy regarding the affirmation of international norms by the Congress. The Charming Betsy doctrine of statutory construction requires national legislation (an American statute) to be construed so as not to raise conflict with international law where possible.

This Article starts from two premises. The first is that power—particularly regulatory power—is increasingly exercised across and between jurisdictions, in particular as a result of the intertwining of economies via trade. The well-being of those involved in the production and trade in goods and services is determined by rules made in multiple jurisdictions, not just their own. Concern about the environmental and social impact of economic activity is a particular reason for jurisdictions to try and impose norms upon each other. The second premise is that the essence of constitutionalism is constitutional values and principles rather than particular institutional forms. Such forms are contingent and instrumental, in the service of the values and principles. Many of those constitutional values and principles are concerned with the exercise of power (e.g., accountability, due process, and non-oppression).

The international arena is increasingly important in EU legal discourse. Using the word “global” is highly fashionable at present, but what does it mean to refer to this concept? It is not an exaggeration to claim that if “constitutionalism” is added to the picture you have a new catchphrase for understanding the EU legal architecture beyond the nation state and its interrelationship with the external sphere: “Global constitutionalism.” Much of the discussion on the normative dimension of EU powers is centered on the function of the EU as a promoter of values abroad. This is also what the Lisbon Treaty promises as set out in Article 3(5) and Article 21 in the Treaty of the European Union (TEU) by guaranteeing, inter alia, that the EU shall uphold its values in the relationship with the wider world and contribute to the protection of its citizens. As witnessed in the recent judgment on the validity of the EU's Emissions Trading System (ETS), the EU's values may sometimes spill over to the global level. In the ETS case, the Court of Justice set out to make a powerful statement on the importance of environmental protection, even when such concerns extend beyond the borders of Europe. Therefore, the question of global constitutionalism in the EU seems inextricably linked to the normative question of what values the EU should promote or conversely “borrow” from the outside world.

The European Union (EU) Emissions Trading Scheme (ETS) is a cornerstone of the European Union's policy to combat climate change and its key tool for the cost-effective reduction of industrial greenhouse gas emissions. Moreover, according to the European Commission, it is the first and biggest international scheme for the trading of greenhouse gas emission allowances, including sophisticated and far-reaching penalties. Notably, however, the scheme arose out of a failure at the international level to agree on global standards. When an amended directive included aviation under this scheme beginning in 2012, it ignited a global controversy that came before the Grand Chamber of the Court of Justice in December 2011. In its decision, the Court and Advocate General explicitly explain that the EU ETS regime arose because of the failure of the International Civil Aviation Organisation (ICAO) to evolve a global regulatory scheme. To some, the decision of the Court of Justice on the EU ETS represents a definitive view on the legality of the EU's ambitions to uphold high environmental standards and to compel others to uphold these standards also.