The title of this book, The Territorial Jurisdiction of the International Criminal Court, does not quite do it justice. The book is an excellent discussion of this aspect of the authority of the International Criminal Court (ICC), but that is not all it is. It is in an important contribution to the understanding of territorial jurisdiction over modern crime, including, but not limited to, the atrocities we call genocide, crimes against humanity, and war crimes. Additionally, this book is a useful contribution to the literature on the sources and evidence of the law applying to international tribunals, and the appropriate application of these materials.

The adjudicative jurisdiction of the ICC – its ‘competence to deal with a criminal cause or matter’Footnote ¹ is set out in a number of provisions of the ICC Statute. The Appeals Chamber of the ICC has interpreted this jurisdiction as having four aspects: subject matter jurisdiction, jurisdiction over persons, temporal jurisdiction, and territorial jurisdiction.Footnote ² The crimes within the subject matter jurisdiction of the court are genocide, crimes against humanity, and war crimes, and, pursuant to amendments adopted in Kampala in 2010 not yet in effect, aggression.Footnote ³ The persons within the jurisdiction of the court are ‘natural persons’ over the age of 18.Footnote ⁴ The court has jurisdiction only over crimes committed after its entry into force.Footnote ⁵

Territorial jurisdiction, however, appears somewhat more obscurely in the ICC Statute. The statute nowhere claims jurisdiction over territory for the court. Instead, in an article headed ‘Preconditions to the exercise of jurisdiction’, it says:

Despite the odd phrasing (‘may exercise its jurisdiction’), both the ICC Appeals Chamber and Professor Vagias have – appropriately in my view – treated this language as defining the territorial jurisdiction of the Court in matters where there is no Security Council referral.Footnote ⁷

Territoriality has been the basis of the ICC's authority over most situations investigated and cases brought in the ICC thus far. This appears likely to continue, as it has proven difficult to gain a consensus at the Security Council to refer situations of mass atrocity to the ICC. Thus, this book addresses issues which are likely to arise in the Court.

This has a problematic consequence, which became the reason for writing this book. Territoriality is a limiting conception of jurisdiction, whereas one ultimate goal of the ICC is broad deterrence of mass violence. Therefore, according to Vagias, a broad view of the Court's authority over its own jurisdiction is appropriate to promote the achievement of the goals of the states which adopted the Rome Statute.Footnote ⁸ The possibility of developing a principled and expansive law of an international criminal court's jurisdiction to decide on the extent of its jurisdiction (‘compétence de la compétence’ in French) is the real motivating factor behind this book.

One of the strengths of this book is that Vagias understands the history of territorial jurisdiction which preceded the modern era of international courts and tribunals. Thus, he does not simply make arguments from the language of the text, the negotiating history of the ICC Statute, and the case law of the Courts. Rather, he examines these in the context of the meaning of territorial jurisdiction as it exists in the wider arena of criminal and regulatory law.Footnote ⁹

While the chapter on the history of territoriality is not long (only 25 pages), it penetrates to the heart of many of the key issues of territoriality. These include the problems surrounding ‘objective’ territoriality, which allows a state to claim jurisdiction where an actor outside the state caused a criminal result (such as a death) within; and the problem of ‘inchoate’ territoriality, where a state claims territorial jurisdiction over outside attempts, conspiracies, etc., intended, but failing, to cause a criminal result in the jurisdiction.Footnote ¹⁰

Vagias also devotes chapters to the negotiating history of the territorial jurisdiction provision of the ICC Statute and to the methods of interpretation appropriate to the provision.Footnote ¹¹ These chapters should prove useful to those studying or working in or before international tribunals generally, not just the ICC. The questions raised, for example, of what materials can properly be used as evidence of negotiating history can recur before any international tribunal facing the question of the meaning of its organic documents.

Where necessary, he makes judgments on controversial issues. One with which this reviewer partially disagrees is his argument that the principle of legality does not apply to the question of whether a matter falls within the territorial jurisdiction of the Court.Footnote ¹² In terms solely of the adjudicative jurisdiction of the Court – its authority to hear cases – Vagias’ view is probably correct. Or perhaps it would be better to say that the principle of legality is not violated just because a broad, rather than a narrow, interpretation of territoriality is applied, bringing some cases within the competence of the Court to decide. After all, the creation of courts to hear cases even after atrocities have been committed has been endorsed by the Nuremberg and Tokyo Tribunals, the International Criminal Tribunals for the Former Yugoslavia and for Rwanda, the Special Court for Sierra Leone, and others.

Legality cannot, however, be abandoned for issues of jurisdiction to prescribe (sometimes called ‘legislative jurisdiction’) – that is, issues of whether the substantive criminal law applied against persons existed at the time that they acted. The UN Secretary-General, the Security Council, and modern international criminal courts and tribunals have accepted as jurisdictional this type of legality challenge.Footnote ¹³

If an expansive reading of territorial jurisdiction were to cause a new criminal prohibition to apply to an actor, which did not apply before the reading, the principle of legality should be invoked in the ICC. This should, however, be a rare event, because it can only occur if the ICC Statute contains substantive crimes which were not already prohibited by customary international law at the time of the act. (Any criminal proscription of customary international law applies to all persons, whether or not they are within the jurisdiction of the ICC; so bringing a person before the Court as to such a crime does not expose them to criminal liability retroactively.) It is at least possible that one progressive provision of the ICC Statute may not yet be a customary international law crime, long-term and severe environmental damage as a war crime.Footnote ¹⁴ Assume an unforeseeable expansion of territoriality were to occur at the ICC, so as to bring someone who was not subject to this prohibition at the time of the act into the ICC to be charged. The principle of legality ought to apply here to allow the actor to argue the issue of whether the application of this prohibition to him or her would be retroactive.

Vagias discusses in detail three major questions regarding the territorial jurisdiction of the Court: How far ‘the conduct in question’Footnote ¹⁵ may extend to acts and criminal results occurring outside the territory of an ICC State Party; whether the ‘effects’ doctrine may extend territorial jurisdiction to states where no element of a crime occurred, but where bad effects of events elsewhere occurred; and how territoriality applies in the case of belligerent occupation.Footnote ¹⁶

Vagias gives all of these excellent, scholarly treatment. The first two of these are questions which arise in many national legal systems, as well as in the ICC. Both scholars and practitioners of ICC and national law can learn from his reasoning and the sources he uses, whether or not they wind up agreeing with his conclusions. For example, many states, especially in civil law countries, have criminal codes defining territoriality very generally. Vagias’ discussion of how to ‘localize’ crime in the context of new challenges, such as using the internet across borders to plan attacks on civilians,Footnote ¹⁷ should be necessary reading for both lawyers and judges at the ICC. Vagias concludes that criminal results which are elements of crimes in the ICC Statute occurring in the territory of a state party justify the exercise of the ICC's territorial jurisdiction. This reviewer finds that his argument convinces, and believes that, when an appropriate case arises, it is likely to be adopted by the Court. Vagias also gives a nuanced and detailed account of the issues involving territorial jurisdiction in cases involving occupied territory. This material is also quite convincing.

This discussion should also be very useful to those who need to apply general language in national codes to new circumstances of transnational crime. Even though the language of most civil law criminal codes differs from that of Article 12(2) set out above, the methods Vagias uses in interpreting the ICC Statute's language will be very illuminating for national lawyers and judges addressing other new challenges of transnational crime, particularly the distinctions he makes in his treatment of national and international sources in constructing possible answers to new questions.

Vagias suggests that the ICC might use a ‘teleological approach’ – an approach based on promoting the underlying goals of the international treaty known as the ICC Statute – to interpreting its jurisdiction in order to adopt the so-called ‘territorial effects’ doctrine of jurisdiction. As he recognizes, this is ‘a highly controversial proposition’.Footnote ¹⁸ The territorial effects doctrine allows a state to take jurisdiction of a crime or regulatory violation under its law where none of the elements (acts or criminal results) of the crime or violation occur on its territory, but where the ill effects spill over into its territory. In the context of the ICC, this would mean taking jurisdiction over crimes committed on the territory of a non-state party, where the ill effects spill over into the territory of a state party. The goal being fulfilled is the prevention and punishment of the worst crimes against individuals and the international community.

The sort of case Vagias imagines is unfortunately a realistic possibility: a state-sponsored campaign of violence wholly within in a state not party to the ICC Statute directed at killing civilians and exterminating the tribe to which they belong. All of the elements of the crime of genocide by killing and the crimes against humanity of murder and extermination would, in this case, be committed outside the territorial jurisdiction of the Court. May the Court nonetheless take territorial jurisdiction under Article 12(2)(a) if these crimes cause large numbers of survivors to flee to a state party, and a refugee crisis occurs there?Footnote ¹⁹ This is a direct, substantial and foreseeable effect of the activity in the state not party, but not an element of the crime of genocide by murder or the crimes against humanity of murder and extermination. (Note that in this example substantive legality is not at issue – the acts are already criminal under applicable customary international criminal law regardless of ICC adjudicative jurisdiction over the case.)

Vagias argues for an extension to international tribunals of a jurisdictional doctrine which is highly controversial even in the national arena. His argument that it is gaining ground as a permissible national practiceFootnote ²⁰ may be useful to anti-trust and securities lawyers as well as to international criminal lawyers. His careful use of these national sources in the service of an argument about authority of an international court based on the text of its organic documents is worthy of emulation. He also recognizes and addresses well the problems of invasion of state sovereignty posed by extending jurisdiction to crimes wholly consummated outside the territorial jurisdiction of states parties to the ICC Statute.Footnote ²¹

In the end, though, even teleological arguments must be based to some extent in the text. It is difficult to see how ‘[t]he State on the territory of which the conduct in question occurred’ can be read to mean a state on which neither the conduct occurred, nor the results of the conduct which define the crime occurred. State practice accepting a ‘non-elemental’ effects doctrine as a matter of general criminal law may be growing, but the evidence that Vagias has collectedFootnote ²² does not prove it is used by states or by international tribunals in the face of this sort of statutory language.

While this review challenges a couple of Vagias’ conclusions, those conclusions concern matters that are worth arguing about. This reviewer still regards this book as an excellent and exceptionally useful contribution to the literature on the ICC and the problem of criminal jurisdiction generally.