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 United Nations was designed to be the central world institution for peace and security, with the Security Council at its core. This chapter looks at the law and history of the UN’s role in international peace and security, along with the secondary role played by the General Assembly. The Security Council is at the intersection of law, politics, and enforcement in world politics. The chapter looks at the formal powers given to the Security Council in the UN Charter and then examines how the practical life of the Council since 1945 has been both more than and less than what the Charter says. Case studies of mass killings in Sudan, Rwanda, and Syria show the limits of Council power under the influence of the US, Russia, and other powerful governments.

Multilateral diplomacy is defined as the management of relations among three or more nation-states, both within and outside international organizations. The main value of multilateral diplomacy is its ability to reduce the complexity of international relations in everyday life, including traveling, sending mail and solving crimes across borders. It produces agreements that are much more practical and less costly than a web of bilateral arrangements between individual countries, and it sets common standards that enable collaboration among scientists, engineers and businesses around the world. In addition to formal international organizations, multilateral diplomacy is practiced in informal or ad hoc groups and coalitions. There are few things in multilateral diplomacy more important than who writes the rules, who sets the agenda, and who holds the pen during negotiations.

The Treaty on the Non-Proliferation of Nuclear Weapons (NPT) is essential for nuclear disarmament and world peace. This chapter compares three dispute-settling mechanisms in the NPT legal complex using the Iran Nuclear Deal (JCPOA) as an example: political measures, non-compliance mechanisms (NCMs), and international courts and tribunals (ICTs). It evaluates the value of each mechanism to ensure Iran’s compliance with its commitments. The discussion includes NCMs like the JCPOA and the UN Security Council regimes and ICT proceedings like ICJ (International Court of Justice) and CJEU (Court of Justice of the European Union). Fact-finding processes at the IAEA (International Atomic Energy Agency) are also emphasized. Finally, the relevance of these models for climate change, environmental protection, and creating a Middle East Weapons of Mass Destruction Free Zone is discussed.

This chapter examines the various mechanisms within the United Nations that deal with human rights. The chapters focus is on the Universal Periodic Review mechanism, but in the process addresses the work of the UN General Assembly, the human rights function of the Security Council through its peace and security mandate, and crucially also of the revamped Human Rights Commission. The chapter looks at the history of its predecessor and assesses how we arrived at the current architecture. The chapter examines specialized procedures, as well as the work of thematic rapporteurs and human rights working groups.

In this chapter, Nigel White assesses the contribution of the UN’s collective security system to the settlement of international disputes. This chapter tests the assumption that impartial law-based dispute settlement by the Security Council is neither achievable because of its political nature nor required by the UN Charter. This chapter analyses the provisions of the Charter and practice of the Security Council in the field of peaceful settlement, looking for evidence of impartiality in both inter-State and intra-State disputes and assessing the influence of peacekeeping mandated by the Council upon impartiality. This analysis shows that the concept of impartiality in peaceful settlement has largely disappeared and asks, in the conclusion, whether it is possible and desirable to (re)turn to impartiality.

This chapter critically examines Palestine’s unsuccessful 2011 UN membership bid. It examines the report of the UN Committee on the Admission of New Members which, under US pressure, could not unanimously recommend Palestine’s membership to the Security Council after examining whether Palestine satisfied the criteria for membership as set out in article 4(1) of the UN Charter. Propelled by this unsuccessful bid, Palestine turned to the General Assembly which upgraded its status to that of a non-Member Observer State in 2012. Although the legal consequences of this upgrade have been considerable, including allowing the State of Palestine to accede to a host of international treaties and multilateral organizations, its juxtaposition against the refusal of the Committee on the Admission of New Members to recommend membership to the Security Council in accordance with the international rule of law is demonstrative, yet again, of the international rule by law principle at work. Although the UN has allowed for a gradual and qualified recognition of Palestinian legal subjectivity over time, its failure to provide the legal and political foundation upon which those rights may actually be realized, namely membership in the Organization, has continued to disenfranchise Palestine and its people.

UN Charter Art. 2:4 aims to protect states from forcible encroachments by other states, but it does not stand in the way of the Security Council taking or authorizing states to take enforcement actions under Art. 42 and did so in the case of Korea 1950 and Iraq in 1991.It may take or authorize enforcement actions – even inside states – under Art.2:7 and 42. It may also under Art. 53 authorize the use of force by regional organizations – and has done so. The Responsibility to Protect (R2P) doctrine envisages the use of force to remedy extreme internal situations, such as genocide or massacres, but only within the rules cited requiring approval by the Security Council. The veto is often criticized as hindering action by the Council. It may, indeed, be excessively used but may sometimes be only a signal from one of the permanent members that it may be ready to use its power to resist an action proposed. Post WWII, force has been used by states – but only rarely – to acquire territory while ignoring the Security Council, notably by North Korea in 1950, Iraq against Iran in 1980 and against Kuwait in 1990, Russia against Ukraine in 2014 and 2022.

The purpose of this chapter is to examine the use of force under the auspices of the UN, in particular the Security Council. Chapter 3 first sets out and examines the relevant provisions of the UN Charter and the division of competence between the various organs of the UN – the Security Council, the General Assembly and the Secretariat – to provide an understading as to how force was originally envisaged as being employed under the auspices of the UN. Given the Security Council’s primacy both within the Charter and in practice, the chapter goes on to examine the specific powers of the Council in relation to the use of forcible measures within the Charter and the limitations imposed upon these. Following this it then examines how these powers and responsibilities have been implemented in practice in both the Cold War and post-Cold War era. In particular, it has developed the practice of ‘authorising’ states, coalitions of states and regional organisations to use force to implement its mandate. The chapter finally addresses the relationship between the UN and regional – and, by extension, collective defence – organisations in the context of the use of force.

This chapter introduces the approach taken in the book, which is to focus on the law, not policy. It further clarifies that the book will focus on the legal aspects of the Security Council based on the UN Charter and in the Council’s practice.

This chapter first looks at four distinct ways in which international law may be developed by and within the Security Council; it then considers the role of the Council in relation to the main sources of international law: treaties and customary international law.

This chapter introduces the jus ad bellum: the rules of law determining when states may resort to war or, more broadly, the use of armed force. These rules must be distinguished from the jus in bello: these are the rules of law that apply in armed conflict (known as international humanitarian law). In order to put the current jus ad bellum rules into perspective, the chapter begins by introducing the concept of collective security and demonstrating how this was applied during the League of Nations era. The following sections set out the relevant rules of the UN Charter on the prevention and regulation of recourse to the use of force, with a particular focus on the prohibition on the threat or use of force. The chapter also discusses the collective use of force, meaning the use of force authorized by the Security Council, and the unilateral use of force in self-defense. Finally, the chapter examines whether new exceptions to the prohibition of the use of force are emerging -- in particular, humanitarian intervention and the responsibility to protect.

This chapter introduces the jus ad bellum: the rules of law determining when states may resort to war or, more broadly, the use of armed force. These rules must be distinguished from the jus in bello: these are the rules of law that apply in armed conflict (known as international humanitarian law). In order to put the current jus ad bellum rules into perspective, the chapter begins by introducing the concept of collective security and demonstrating how this was applied during the League of Nations era. The following sections set out the relevant rules of the UN Charter on the prevention and regulation of recourse to the use of force, with a particular focus on the prohibition on the threat or use of force. The chapter also discusses the collective use of force, meaning the use of force authorized by the Security Council, and the unilateral use of force in self-defense. Finally, the chapter examines whether new exceptions to the prohibition of the use of force are emerging -- in particular, humanitarian intervention and the responsibility to protect.

The debate on the compatibility of neutrality with collective security appears to have occupied scholars in the interwar period but not after the end of World War II. However, it remains relevant. Neutrality defers to collective security only if the Charter mechanism works effectively. Even then, however, neutrality is admissible if it does not subvert collective action authorized by the Security Council or the General Assembly under the Uniting-for-Peace resolution.

Upon Britain’s withdrawal from Palestine, a Jewish state was declared, and military forces from neighboring Arab states entered Palestine. In the Security Council, the Provisional Government of Israel charged aggression on the part of the Arab states and asked for Security Council action to stop it. The Arab states denied aggression, saying that they entered Palestine at the request of its population for the purpose of protecting that population from further acts of expulsion. Syria invoke the doctrine of humanitarian intervention as a rationale for the actions of the Arab state forces. The Provisional Government of Israel said that the aim of the Arab state intervention was the dismantling of Israel as a state. The Security Council took no action on the charge of aggression. The Security Council called for ceasefires.

While the General Assembly was considering whether to recommend partitioning Palestine, the Arab states that were UN members asked the General Assembly to submit to the UN judicial arm, the International Court of Justice, the question of the legitimacy of partition. This proposal was backed by nearly half of the UN membership but failed of passage. The International Court of Justice has the power to issue a non-binding opinion on any legal question put to it by the General Assembly or Security Council. After a Jewish state was declared, Syria made a proposal in the Security Council to seek such an advisory opinion on the legal status of Palestine upon Britain’s withdrawal, and the legitimacy of the Jewish state that was declared at that time. Syria’s view was that Palestine as a single entity automatically acquired independence upon Britain’s withdrawal. It proposed an advisory opinion in the expectation that the International Court of Justice would agree. In initial discussion of this proposal in the Security Council, several members spoke in its support. A vote on the proposal was put off to a future meeting.

The reliance by the Provisional Government of Israel on the General Assembly’s resolution on partition was challenged on the grounds that the Provisional Government of Israel did not confine itself to the borders proposed in that that resolution. The Security Council asked the Provisional Government what borders it claimed. The Provisional Government of Israel said that it claimed the territory contemplated for a Jewish state by the General Assembly’s resolution, and that it was holding territory beyond those lines as belligerent occupant only. Through 1948, the Provisional Government of Israel gained more territory beyond the borders of the General Assembly’s resolution. The Security Council called on all parties not to gain additional territory in Palestine. In 1949, armistice agreements were concluded, leaving Israel in control of territory beyond the borders of the General Assembly resolution. The Government of Israel then claimed sovereignty over these territories. That included territory within the city of Jerusalem.