This article, based on a lecture offered in honour of Professor Cleveringa, provides some insights into the difficult question of ‘unjust laws’ and the place of ethics in law, with an emphasis on international law. While this question has long been a bone of contention between natural lawyers and positivists, it has a particular importance in international law. Attention is paid to the role of ethics in the context of non-discrimination and armed conflicts.

In this article I am interested in seeing what the normative jurisprudential support is for a minimalist version of habeas corpus in international law. I investigate what Fuller called ‘procedural natural law’ in contemporary international criminal law. In the first two sections I rehearse some of Hart's and Fuller's views as they pertain to the subject of international law and also to the inner morality of law. In the third section I set out some of my views on these matters, drawing on both Hart and Fuller, concerning the value of fundamental procedural rights. In the fourth section I discuss the right of habeas corpus as a good test case of how to think about these issues. In the final sections I expand on these remarks and argue that procedural rights need to be protected better in international law, if the latter is to have a claim to legitimacy as a mature legal system.

The principle of complementarity is one the cardinal features of the architecture of the Rome Statute. Complementarity provides not only a forum to advocate overlapping competencies and litigate jurisdictional disputes over admissibility (e.g. Articles 17 and 19), but marks the foundation of the Statute as a multidimensional system of justice (e.g. Preamble, Article 1). This topic has been a focus of attention of the Court since its very inception. When taking office, the Prosecutor of the International Criminal Court (ICC), Luis Moreno-Ocampo, qualified complementarity as one of the key factors for the successful operation of the Court, noting that ‘the absence of trials led by [the] Court as a consequence of the regular functioning of national institutions would be a major success’. As of 2003, the Office of the Prosecutor (OTP) has developed guidelines and principles on complementarity in order to clarify its theoretical underpinnings and operational features.

The admissibility challenge of the defence in Katanga has raised complex issues of litigation in the light of the practice of self-referrals and existing ICC jurisprudence. This article examines the Katanga Trial Chamber decision and its consequences from this perspective. It focuses on three themes that are of particular relevance, since they have a direct impact on the functioning of the Court and its different organs: (i) the timing for a challenge of the admissibility of the case; (2) access to information related to admissibility; and (iii) the role of the defence.

This commentary argues that the Trial Chamber in Katanga adopted an erroneous interpretation of the Statute of the International Criminal Court by limiting the grounds to ne bis in idem on which a challenge to admissibility can be brought after the confirmation of charges. The Trial Chamber held that the ‘commencement of trial’ under Article 19(4) is the moment of the constitution of the Trial Chamber, rather than the making of opening statements. This commentary re-examines the legal reasoning of the Court and advocates a different reading. It also suggests that the Chamber has failed to strike a proper balance between the possibility of making challenges to admissibility and the smooth and efficient working of the proceedings, which compromises the long-term legitimacy of the institution and the interests of justice.

This article examines the judgment on Kantaga's appeal against the decision of Trial Chamber II of the International Criminal Court that the case against him was admissible. The Appeals Chamber rejected Katanga's appeal, and affirmed the admissibility of the case. However, it did not do so on the same basis as the Trial Chamber (that the Democratic Republic of the Congo (DRC) was unwilling). Rather, it looked at the plain language of Article 17, and found that at the time of the challenge the DRC was not investigating or prosecuting Katanga. This judgment can be seen as an example of judicial restraint. The Appeals Chamber dealt only with those questions which were necessary to dispose of the appeal. It did not engage in policy debates or seek to create new facts, but rather applied the Statute as drafted to the facts of the case before it. In doing this, the Appeals Chamber confirmed certain basic principles of the admissibility regime. The case also provides an insight into the relationship between admissibility and ‘positive complementarity’.

On 25 September 2009, the Appeals Chamber of the International Criminal Court (ICC) issued a seminal decision on the subject of complementarity in the case Prosecutor v. Germain Katanga. The outcome of the Chamber's decision is that, even if a state has initiated an investigation or prosecution against an individual, the ICC may prosecute that individual for the same crimes or even a more selective range of crimes, so long as the state is willing to close the ongoing investigation or prosecution at the request of the ICC Prosecutor. While this decision is defensible under the language of the Rome Statute, this article concludes that, absent vigilance on the part of the ICC's Office of the Prosecutor, the decision could produce consequences inconsistent with the principle that the ICC is intended to act as a court of last resort. These potential consequences, in turn, suggest that the prosecution's policy of ‘positive complementarity’ – that is, encouraging genuine national proceedings whenever possible – should be at the core of its case selection strategy. At the same time, in those instances when the ICC prosecution determines that, despite activity by a national system with respect to a particular case, it is appropriate for the ICC to take over the case, the prosecution should clearly and publicly explain the factors that led to its decision.

Like all rules of customary international law, those existing in the field of international investment law are binding on all states. According to the theory of the persistent objector, however, a state is not bound by a rule if it objected to it in the early stages of its formation and continued to do so consistently thereafter. This paper analyses the different grounds of criticism that have been raised against the concept. We found that there is only very weak judicial recognition of the concept, that there is no actual state practice supporting it, and that it is logically incoherent. Specifically, this paper argues that the concept should not be successfully used in investor–state arbitration proceedings to prevent the application of a custom rule by an arbitral tribunal. This is essentially because of the great importance of the few custom rules existing in that field and the fact that they represent universally recognized values.

Investment treaty arbitration, unlike commercial arbitration, is not a purely private dispute settlement mechanism that is entirely subject to party autonomy and limited in its effects to the parties to the proceedings. Rather, it fulfils a public function in influencing the behaviour of foreign investors, states, and civil society more generally by crafting and concretizing international standards of investment protection. Investment treaty arbitration thus implements and operates as part of a public system of investment protection. Arbitrators, as a result, incur obligations not only towards the parties to the proceedings, but vis-à-vis the whole system of investment protection. These obligations can be conceptualized as part of the public law implications of investment treaty arbitration and affect, inter alia, the role and status of arbitrators in investment treaty disputes, the procedural maxims that such arbitrations should follow, and the way arbitral awards should be crafted.

The year 2009 was one of many anniversaries for the state-building project. It marked ten years since the United Nations began its bold experiments of state-building in East Timor and Kosovo, now the independent state of Timor-Leste and the embryonic Republic of Kosovo respectively. It was twenty years since Namibia held elections in the course of becoming independent, heralding a new post-Cold War activism. It was also ninety years since the League of Nations established the mandate system, which – even though it applied only to the colonies of enemy states defeated in the Great War – marked the beginning of the end of colonialism.

A new genre of scholarly writing has emerged in recent years in the field of what one can broadly call critical international theory. Its principal defining feature is an intense preoccupation with the phenomenon of the so-called ‘new world order’, which it tries to explain and describe through an analytical lens constructed primarily around two ideas: the idea of ‘empire’ and the idea of ‘imperial law’. In this article I attempt to provide a brief overview of this genre, which for the sake of simplicity I shall call henceforth the ‘new imperial law’ or NIL genre, and to reflect critically on its underlying ideological dynamics.