This chapter discusses the immunities of individuals in relation to criminal prosecution for international crimes. It introduces the main two types of immunity: functional immunity and personal immunity. It discusses diplomatic immunity as a particular illustration. The chapter then discusses limits on functional immunity, with the Pinochet decision and other precedents. It then discusses the harder situation of personal immunity, as explained by the International Court of Justice in the Arrest Warrant Decision. It reviews various ways that states have relinquished immunity, including through Security Council resolutions under Chapter VII of the UN Charter, or through ratification of the ICC Statute. The chapter surveys the many issues about whether Security Council referrals to the ICC, coupled with a duty to cooperate fully, have the same effect of removing immunity. The chapter then discusses the legal position advanced by the Sierra Leone Special Court in the Taylor case, and endorsed by the ICC Appeals Chamber in the Al Bashir case, that there are no immunities before international courts, by virtue of their special nature. The chapter canvasses criticism of the theory as well arguments in favour of it.

The chapter situates the class of institutions variously referred to as internationalized, hybrid, mixed or special tribunals in the system of international criminal justice and highlights their main rationales and features. It addresses the known strengths and weaknesses of the hybrid institutional model as compared to purely international criminal jurisdictions. Using the classification based on these courts’ legal nature as defined by the primary basis for their establishment and functioning, the chapter surveys the main hybrid courts (including some which are yet to be established), including but not limited to the Special Court for Sierra Leone, Special Tribunal for Lebanon, Extraordinary African Chambers, the African Criminal Court, the UNTAET and UNMIK Special Panels (in East Timor and in Kosovo, respectively), the Kosovo Specialist Chambers, and the Special Criminal Court in the Central African Republic. It outlines the factual background to these courts’ emergence and addresses their subject-matter jurisdiction and applicable law, institutional and procedural features, and noteworthy contributions to international criminal jurisprudence. This overview is followed by the discussion of the issues raised by the hybrid courts’ (potential) relationship with the ICC and reflections on their achievements, deficiencies, and (the prospects of) wider impact.

The chapter discusses the position of victims in international criminal justice and the evolution of their status and modalities of their involvement in the administration of justice by international criminal jurisdictions, with a particular focus on the legal regime of the International Criminal Court (ICC). The chapter highlights the centrality of victims as the core constituency of international criminal law and the mismatch between this aspiration and the limited recognition of their agency and rights before the UN ad hoc tribunals. It then examines how the ICC’s architects have sought to bridge this gap in the Court’s Statute and Rules of Procedure and Evidence. The ICC’s legal framework is unprecedented in this respect. Over and above the protective measures necessary on account of their engagement in the proceedings, it granted victims extensive rights to participate and be legally represented at different stages the ICC proceedings as well as the autonomous right to obtain reparations. The chapter surveys the key challenges this ambitious scheme has raised, as far as the admission of victims to participate, the organisation of their legal representation, and the implementation of reparations are concerned, and solutions that have been developed in the Court’s practice to date.

This chapter introduces the law of war crimes including: its historic development, common legal issues such as identifying an armed conflict, and the specific offences constituting war crimes. As for the historic emergence of war crimes law, the chapter looks at the evolution of humanitarian law – on which war crimes law is based. The chapter discusses the key principles of humanitarian law (distinction, proportionality, etc), the challenges of regulating warfare, the emergence of individual criminal responsibility (i.e. war crimes), and the evolution of war crimes in non-international armed conflicts. As for ‘armed conflict’, the chapter discusses common challenges in identifying the character of the armed conflict (international or non-international), for example in situations of invitation, national liberation, proxy forces, and transnational conflict. The chapter reviews the requirements to qualify as an armed conflict – intensity of the conflict and organization of the parties. It then reviews specific illustrations of war crimes, including: crimes against non-combatants (killing, sexual violence, experiments, and so on); attacks on prohibited targets (for example, historic monuments, hospitals, and so on); and attacks likely to inflict disproportionate civilian harm compared to the anticipated military advantage; prohibited weapons; and prohibited methods of warfare.

The chapter presents an overview of the procedural arrangements adopted at the international criminal jurisdictions, namely the UN ad hoc tribunals for the former Yugoslavia and Rwanda and the International Criminal Court (ICC), covering the main milestones from the initiation of the investigation to trial phase to appeals against the judgment and sentence and review. Before delving into the trajectories of an criminal case before international criminal courts and tribunals, the chapter highlights the origins of international criminal procedure in the common law (Anglo-American, or ‘adversarial’) and civil law (Continental, or ‘inquisitorial’) approaches, resulting in its legal nature as a hybrid scheme where the balance between the domestic influences varies by tribunal and over time due to reforms pursued by judge-legislators (ICTY and ICTR) or by states and, to a lesser extent, judges (ICC). The chapter reviews the role and functions of the main actors in international criminal proceedings, including repeat or professional players (judges, prosecutors, and defence) and other participants such as victims and witnesses and states and international organisations. It also highlights the normative importance of human rights to international criminal process and the imperative of complying with the principles of public, fair and expeditious proceedings.

This chapter delves into the application of trapped ions in electromagnetic fields for quantum computing, starting with the technique of confining ions using a linear Paul trap. It then examines the encoding of qubits within the ions’ electronic states. The interaction between an ion and a laser, pivotal for system operations, is analyzed next. This interaction underpins the initialization of ions via laser cooling and the execution of one- and two-qubit gates. The two-qubit gates also employ the ions’ motional states to extend beyond the traditional qubit space. The process also includes a method for measuring qubit states by detecting the photons released when ions are excited. The text identifies key sources of noise that can affect ion traps. It concludes with a summary and the advantages and challenges associated with trapped-ion quantum computing.

This chapter examines the use of photon ensembles for quantum computing. It opens with a primer on photons, normal modes, and both linear and nonlinear optics. The discussion then advances to the technologies employed in generating and detecting single photons, followed by methods of qubit encoding and initialization. Subsequently, the focus shifts to qubit control, detailing the execution of single-qubit gates using linear optical elements and the Knill–Laflamme–Milburn (KLM) protocol for two-qubit gates. While the textbook predominantly centers on the circuit model, alternative models of quantum computing – specifically, one-way quantum computing and continuous-variable quantum computing – and their optical implementations are introduced. Additionally, it outlines the primary sources of noise affecting these systems. The chapter wraps up with a reflection on the comparative benefits and limitations of optical quantum computing.

This chapter delves into superconducting qubits, starting with the essentials of superconductivity and circuit design. Central to this discussion is the Josephson junction, a key element in creating superconducting qubits. The text focuses on the transmon, the archetype in this field, while acknowledging other designs. Initialization of the transmon involves sophisticated dilution refrigerators, a process that is also examined. Additionally, the principles of circuit quantum electrodynamics (QED) are introduced as the framework for qubit control and measurement. Attention is then given to noise sources and their effect on superconducting qubits, with insights that apply to various qubit systems. The chapter wraps up by highlighting the strengths and challenges of superconducting qubits for quantum computing.