It is tempting to introduce this special section in an apologetic tone. Has not enough been written, in recent years, on constitutionalization, that new phenomenon and term which has recently entered the world of politics and law, closely related to global constitutionalism, to constitutionalism in international law? And is there really a need to publish another three articles on Hans Kelsen, Carl Schmitt, and Hannah Arendt, instead of highlighting new faces and frames of thought in international law and its theory?

While today a significant stream of European scholarship of international law is concerned with the process and consequences of its constitutionalization, criticism of this trend has so far been muted. This article, using elements of the Pure Theory of Law, argues that constitutionalist writings confound methodologies, that scholarship claims competencies which it does not have, and that this confusion diminishes the benefits of the constitutionalist project for international law. The key problem is called a ‘methodological circle’: scholars call something a constitution and in effect claim that the law is changed by this classification. Thus constitutionalism relies on the natural law concept of practical reason; constitutionalism is, in turn, vulnerable to Kelsen's arguments against practical reason. Constitutionalism, like practical reason before it, contains an impossible admixture of the human faculties of will and cognition. The general critique is followed by a look at Article 2(6) of the UN Charter as a case in point. Here constitutionalism shows how law is purportedly changed by taxonomy. The article concludes by taking a look at an alternative vision of the constitution of international law: the rediscovery of a strictly legal – that is, structural – constitution as the highest echelon of legal regulation.

Carl Schmitt is still astonishingly present in the legal discourse. Yet instead of indulging in the study of his explicit ‘lesson’ and its possible impact on contemporary legal problems, it might be worthwhile to survey the primary cause of his greatest fear. Following this perspective, the article analyses Schmitt's concept of the nomos, distinguishing it from the traditional normativist approach on the one hand and confronting it with a more recent understanding of law in terms of the network conception on the other. Thus Schmitt's view of the developing legal system in the twentieth century proves to be relevant to our current efforts to grasp newly emerging legal phenomena in the twenty-first century.

‘What is politics?’ is an omnipresent question in Hannah Arendt's work and one which is broadly explored in countless publications. ‘What is law?’, in contrast, is a question which has not been of much interest to Arendt scholarship to date. There is a good reason for this: Arendt's engagement with law seems not to be systematic but, rather, episodic and sporadic. However, on the basis of three different discourses – historical, political-theoretical, and legal-philosophical – I shall point out that Arendt's dealing with legal questions takes place on a continuous basis and should be regarded as crucial for a proper understanding of her thoughts. I shall argue that with her shift from the Greek conception of law as nomos to the Roman lex, Arendt seeks to de-substantiate the concept of law and to highlight the relationship-establishing dimension of law. Both attempts are important for overcoming the dichotomy of law and politics within constitutionalism and for paving the way to a different understanding of legal rationality which seeks not to isolate law from the political sphere but rather to interact with it.

The article revisits the Barcelona Traction judgment of the International Court of Justice, rendered forty years ago. It evaluates the lasting influence of the Court's pronouncements on the nationality of corporations and on obligations erga omnes, and uses the case to illustrate the Court's role as an influential agent of legal development. In this respect, it identifies a number of factors that can help to explain under which circumstances judicial pronouncements are likely to shape the law.

With a looming referendum on the secession of South Sudan, the drafters of the Abyei Arbitration Agreement were faced with a complex intra-state dispute and a limited time to resolve it. The parties to the dispute agreed on a procedural regime to govern the arbitration, combining both traditional and innovative provisions on procedural rules, the constitution of the tribunal, the schedule of pleadings, transparency, financing of the proceeding, and the role of the Permanent Court of Arbitration. This article examines the key provisions of the Abyei Arbitration Agreement and their implementation during the course of the arbitration, and evaluates the case's significance as procedural precedent for future intra- or inter-state arbitration. The article does not provide an analysis of the substantive findings of the tribunal.

Of the three existing core crimes in international criminal law, crimes against humanity is the most elusive one, a chameleonic crime that can change colour over time, since it does not possess an unambiguous conceptual character. The characterizing element of genocide obviously is the specific intent to destroy. War crimes must have a nexus with an armed conflict. The identifying element of crimes against humanity is more difficult to pin down as the contextual elements have changed over time.

This article argues for amending the Rome Statute to remove the state or organizational policy requirement from the classification of crimes against humanity. After a brief look at the requirement itself, the article presents arguments to show how the policy loophole creates an accountability loophole in international criminal law, and how removing it both resolves inconsistencies in the Rome statute and facilitates prosecutions for international crimes. The article's final section examines and responds to leading arguments for keeping the policy requirement. The article is intended to show how the policy requirement limits international criminal law's scope in unwelcome ways and to challenge the use of state or organizational policy as a dividing line between domestic and international crimes.

In this commentary to Matt Halling's paper, the author takes issue with Halling's proposal to amend Article 7(2) of the Rome Statute with regard to the ‘policy element’. Halling's view of plugging ‘loopholes’ in the Rome Statute in abstracto is met with a voice of realism. The author's realism is expressed on different levels and can be summarized in the following questions. As to the need for an amendment of Article 7(2), how realistic are the scenarios presented by Halling? Do they really call for an amendment? As to the function and role of the court, why expand the Court's mandate when it can only prosecute a handful of cases at any one time? As to the Court prosecutorial policy, does the Court need a fine net when it has limited resources and a mandate that requires it to focus on those who bear the greatest responsibility?

At the beginning of the renaissance of international criminal law in the 1990s, the law on crimes against humanity was in a fragile state. The International Criminal Tribunal for the former Yugoslavia (ICTY) decisively contributed to the consolidation of customary international law on crimes against humanity and paved the way for its first comprehensive codification in Article 7 of the Statute of the International Criminal Court (ICC). At the same time, the ICTY in its early decisions already showed a certain inclination to broaden the scope of the application of the crime by downgrading its contextual requirement. More recently, this tendency culminated in the complete abandonment of the policy requirement. While this ‘progressive’ facet of the ICTY's jurisprudence largely took the form of obiter dicta, the Situation in the Republic of Kenya has confronted the ICC with the need to ‘get serious’ about the present state of the law. This has led to a controversy in Pre-Trial Chamber II about the concept of organization in Article 7(2)(a) of the Statute. While the majority essentially follows the path of the more recent case law of the ICTY, the ICTR, and the Special Tribunal for Sierra Leone and supports a liberal interpretation, Judge Kaul prefers to confine the term to state-like organizations and generally calls for caution against too hasty an expansion of the realm of international criminal law stricto sensu. This comment agrees with the main thrust of the Dissenting Opinion and hopes that it will provoke a thorough debate.

On 11 June 2010, the first Review Conference of the International Criminal Court (ICC) adopted Resolution RC/Res. 6 on the ‘Crime of Aggression’ by consensus, after years of debates and negotiations in the framework of the Preparatory Commission for the International Criminal Court and the Special Working Group on the Crime of Aggression. The resolution includes a definition of the crime of aggression and the conditions under which the Court could exercise jurisdiction with respect to the crime, while making the actual exercise of jurisdiction ‘subject to a decision to be taken after 1 January 2017’ by states parties. This outcome has triggered a broad variety of reactions. The UN praised it as a ‘historic agreement’ and a significant step towards a new ‘age of accountability’. Some non-governmental organizations (NGOs) have expressed concerns that the compromise deepens the gaps between states and leaves accountability loopholes. US legal advisor Harold Koh qualified the compromise as an opportunity for further constructive dialogue and positive engagement with the ICC.

This contribution sets out the path towards consensus at Kampala. Before the Review Conference, two main issues remained unresolved: the question whether some form of consent by the alleged aggressor state should be required, and the role of the UN Security Council. Few had expected a consensus on a comprehensive package. The outcome of Kampala reflects significant compromises, but also a significant step to advance international criminal law.

The authors participated in the ICC Review Conference held in Kampala in June 2010, which adopted by consensus a package agreement on the crime of aggression. This contribution presents some impressions from these negotiations. It was rather unexpected that consensus agreement could be reached, and the authors offer some explanations why this was possible. They also analyse the key elements of the agreement. After the international criminalization of aggression has been debated for decades, a decisive step has now been taken towards bringing this crime within the effective jurisdiction of the International Criminal Court.

Four discrete issues demonstrate how complex the crime of aggression under the Rome Statute of the International Criminal Court will be following the amendments approved in Kampala in June 2010. First, the absence of an explicit magnitude, or gravity, requirement for determining an act of aggression ignores the reality of how matters are referred to the ICC as well as how one first determines the existence of aggression. The gravity test of a crime of aggression is insufficient and misleading in arriving at a methodology for a logical determination of both acts and crimes of aggression. An agreed understanding in Kampala to resolve the dilemma is fraught with contradictions. Second, the amendments fail to address how the ICC should respond to a Security Council determination that an act of aggression has not occurred. Third, the lingering debate over how the Rome Statute should have been amended to activate the crime of aggression will burden the Assembly of States Parties, which should focus on arriving at a united interpretation of the procedures used to approve the Kampala amendments. Fourth, given the many permutations of how states will fall within or outside the jurisdiction of the International Criminal Court regarding the crime of aggression, the resulting patchy landscape of coverage should surprise no one.

The International Military Tribunal at Nuremberg established a legal precedent for the proposition that waging a war of aggression is an international offence, for which individuals may be held criminally accountable. The efforts of the First Review Conference of the Rome Statute have resulted in a definition of the crime of aggression being included in the Rome Statute. Although a framework for the International Criminal Court's exercise of jurisdiction over the crime of aggression was also included in the amendments adopted at the Review Conference, such exercise of jurisdiction has not been given immediate effect and is subject to further action by the members of the Assembly of States Parties.

This article argues that the principle of judicial economy belongs to the fundamental canons of international procedure – that is, those canons which are inherent in the judicial function and whose application should generally be ensured by the judge concerned, regardless of what the written procedural law establishes. This is particularly evident if one considers how often international courts and tribunals, precisely for reasons of judicial economy and departing from the duty to decide all points put forward by the parties (non ultra petita), enter into those issues alone which are necessary for the purpose of resolving the dispute and/or establishing the true state of the world (the so-called criterion of judicial limitation of the scope of the decision or absorption). Even though no provision requires it, each judge is in fact expected to operate in conformity with this criterion and to use it in a proper way; its misapplication may lead to reforming the decision or precluding its enforcement. The frequent use of the criterion at issue, on the other hand, supports this article's final contention, according to which judicial economy is an expression of judicial activism.

For decades it has been authoritatively stressed that non-justiciability of defence and foreign affairs represents one of the major hurdles to the application of international law by domestic courts. Until now, however, international law scholarship seems to have overlooked two aspects of this issue. First, it has not been sufficiently highlighted that the international and the European community legal orders are progressively eroding the scope of application of these non-justiciability doctrines. Second, it has rarely been shown how judicial intervention in international matters can be prevented from turning into the ‘judicialization’ of foreign policy. Hence, ideally by moving along the path traced by those who have already dealt with this issue, the present work aims to analyse these two aspects in greater depth.