Public International Law (LLB)

# Public International Law (LLB) — Topic Notes
## Exam format: 4 essays from 8 (UOL format, Zone A / Zone B sittings)

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## 1. JURISDICTION AND STATE IMMUNITY

### 1.1 The Restrictive Doctrine of State Immunity

State immunity is the principle that courts of one state will not "implead a foreign sovereign … whether the proceedings involve process against his person or seek to recover from him specific property or damages." The general rule is codified in **State Immunity Act 1978 (SIA), s.1(1)**: a State is immune from UK court jurisdiction except as provided in the Act.

The modern **restrictive doctrine** distinguishes *acta jure imperii* (sovereign acts, immune) from *acta jure gestionis* (commercial acts, not immune).

**Key case — commercial exception:**
- *SerVaas Incorporated v Rafidian Bank and others* **[2012] UKSC 40**: The Supreme Court construed s.13(4) SIA — the exception for "property in use or intended for use for commercial purposes." SerVaas sought to attach Iraqi bank assets held in England to satisfy a judgment arising from a copper factory supply contract. The SC held that whether property is "for commercial purposes" must be assessed by reference to the specific property, not the underlying transaction. Frozen bank assets in satisfaction of a sovereign debt did not qualify as commercial-purpose property; Iraq retained immunity. **Ratio**: the commercial exception to enforcement immunity under SIA s.13(4) is construed narrowly — the property's current or intended use must itself be commercial.

**Key case — state immunity and employment claims (ECHR interface):**
- *Benkharbouche v Secretary of State for Foreign and Commonwealth Affairs* **[2017] UKSC 62**: Domestic staff employed at foreign embassies in the UK sought to bring employment claims. SIA s.4(2)(a) barred claims by embassy domestic staff. The Supreme Court (Lord Sumption) held SIA s.4(2)(a) was incompatible with ECHR Art.6 (right to a fair trial) and EU law (Charter of Fundamental Rights Art.47). The UK courts were obliged to disapply the SIA provisions to the extent of incompatibility with EU law. **Ratio**: State immunity under the SIA is not absolute — where the SIA denies access to court without justification, ECHR Art.6 / EU Charter Art.47 can require disapplication.

**Key case — definition of "commercial purposes" (immunity from execution):**
- *Argentum Exploration Ltd v Republic of South Africa* **[2024] UKSC 16**: Argentum salvaged silver bullion from a WWII wreck. The silver had belonged to South Africa and was intended for coinage. The SC held the silver was not "in use or intended for use for commercial purposes" under SIA s.13(4) — coinage is an exercise of sovereign authority. South Africa retained immunity from the salvage claim. **Ratio**: even property transported commercially retains immunity if its purpose is inherently sovereign.

**Key case — employment and state immunity (Vienna Convention diplomatic immunity distinguished):**
- *The Kingdom of Spain v L Lorenzo* **[2023] EAT 153**: The Employment Appeal Tribunal, following *Benkharbouche*, held that diplomatic immunity under VCDR Art.31 (Vienna Convention on Diplomatic Relations) is personal to the *diplomat*, not a defence available to the *sending State* as respondent to employment discrimination claims. Consistent with *Benkharbouche*, SIA s.4(2)(a) was disapplied as contrary to EU law. **Ratio**: diplomatic immunity under VCDR Art.31 does not automatically confer state immunity on the sending State in employment proceedings.

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### 1.2 Head of State Immunity and the Pinochet Principles

**Key case (principles stated in):**
- *Harb v HRH Prince Abdul Aziz* **[2014] EWHC Ch 1807**: The court restated three tiers of immunity:
  1. A serving head of state has **absolute personal immunity** (*ratione personae*) — covering all acts, public and private.
  2. A former head of state has narrower **functional immunity** (*ratione materiae*) — covering only official acts done in office; private obligations are not protected.
  3. By reference to the Pinochet litigation: a former head of state **cannot claim immunity for torture** — torture cannot be an "official act" because the Torture Convention 1984 (to which Chile was signatory) requires states to criminalise it; to grant immunity would frustrate the Convention's object. **Ratio**: former head of state immunity is limited to *official* acts; torture is not an official act capable of attracting immunity.

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### 1.3 State Immunity in Arbitration / Investment Treaty Enforcement

- *Spain v Infrastructure Services Luxembourg* **[2026] UKSC 9**: The Supreme Court determined that foreign sovereign states cannot invoke SIA s.1 to resist registration of ICSID awards under the Arbitration (International Investment Disputes) Act 1966, because the ICSID Convention (to which the UK, Spain and Zimbabwe are parties) imposes a direct obligation on contracting states to recognise and enforce awards. Sovereign immunity yields to the treaty obligation. **Ratio**: ICSID Convention Art.54 creates a self-contained enforcement regime that overrides SIA immunity.

- *Border Timbers Limited v Republic of Zimbabwe* **[2024] EWHC 58 (Comm)**: Zimbabwe asserted SIA immunity to resist a registered ICSID award of US$124 million for expropriation of land. The Commercial Court held Zimbabwe fell within the SIA exceptions (submission by treaty and/or commercial property exception). **Ratio**: A state party to ICSID that has not paid an award may be pursued in English courts; immunity exceptions under the SIA must be construed in light of international treaty obligations.

- *CC/Devas (Mauritius) Ltd v Republic of India* **[2025] EWHC 964 (Comm)**: India resisted enforcement of BIT arbitration awards arguing the New York Convention (NYC) ratification did not constitute "prior written agreement" to English court jurisdiction under SIA s.2(2). The court held NYC ratification *does* constitute such consent for enforcement purposes. **Ratio**: A state's treaty membership of the New York Convention amounts to submission to jurisdiction for enforcement of foreign arbitral awards under SIA s.2(2).

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## 2. SOURCES OF INTERNATIONAL LAW

The corpus does not contain ICJ decisions. The following principles are derived from UK domestic cases which apply or discuss international law sources.

### 2.1 Custom and the Role of Treaties

- Custom requires (1) *state practice* (consistent, widespread, general) and (2) *opinio juris* (the sense of legal obligation). This is derived from the ICJ's *North Sea Continental Shelf Cases* (1969) — authoritatively discussed in UK courts whenever custom is in issue.

- UK courts engage with customary international law as part of common law: the *Benkharbouche* litigation involved the court asking whether SIA s.4 reflected or departed from customary international law on state immunity, demonstrating how domestic cases interrogate custom.

### 2.2 Treaties in UK Law

- International treaties bind the UK at the international level on ratification; they do not automatically become part of domestic law (dualist system). Incorporation requires an Act of Parliament (e.g. SIA 1978 incorporates the 1972 European Convention on State Immunity principles; the Human Rights Act 1998 incorporates ECHR rights).

- *Lysongo v The Foreign and Commonwealth Office* **[2018] EWHC 2955 (QB)**: Claimant sought declarations that the union of British Southern Cameroons with Cameroon was illegal, and that the FCO had breached international law and UN resolutions. The High Court struck out the claim — English courts lack jurisdiction to adjudicate inter-state violations of international law or UN resolutions at a claimant's suit. **Ratio**: UK courts cannot enforce international law obligations owed between states as if they were private rights.

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## 3. DISPUTE SETTLEMENT — ICJ JURISDICTION & ARBITRATION

### 3.1 ICJ Framework (treaty-based sources; no ICJ cases in UK corpus)

ICJ jurisdiction is founded on: (a) the optional clause (ICJ Statute Art.36(2)); (b) special agreement; (c) jurisdictional clause in a treaty. Advisory opinions are non-binding but authoritative.

### 3.2 International Arbitration in UK Courts

- *PAO Tatneft v Ukraine* **[2018] EWHC 1797 (Comm)**: Ukraine challenged enforcement of a US$112m BIT arbitration award on the basis it had not submitted to arbitration under the relevant bilateral investment treaty, and separately argued SIA immunity. The court examined whether the BIT's arbitration clause constituted submission to jurisdiction for SIA purposes (s.9 SIA). **Ratio**: A state's agreement to arbitration in a BIT constitutes a waiver of immunity for enforcement proceedings under SIA s.9, provided the claim falls within the scope of the treaty's arbitration clause.

- *Hulley Enterprises v The Russian Federation* **[2023] EWHC 2704 (Comm)**: Enforcement of US$50bn+ PCA awards against Russia in English courts; preliminary issues on whether Dutch court judgments on jurisdiction estopped Russia from re-arguing. **Ratio**: Issue estoppel principles apply between states in investment arbitration enforcement proceedings; prior judicial determinations of jurisdictional issues bind in subsequent enforcement courts.

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## 4. INTERNATIONAL CRIMINAL LAW — EXCLUSION FROM REFUGEE PROTECTION

The Refugee Convention 1951 Art.1F(a) excludes from protection persons for whom there are "serious reasons for considering" they have committed crimes against peace, war crimes, or crimes against humanity.

- *AB v Secretary of State for the Home Department* **[2020] UKUT 268 (IAC)**: Iraqi doctor worked in Libya for four years. The War Crimes Unit excluded him from Convention protection under Art.1F(a). The Upper Tribunal had to consider the standard of proof and what conduct amounts to complicity in crimes against humanity. **Ratio**: Art.1F(a) exclusion applies where there are serious (but not conclusive) reasons for believing the person was complicit in internationally defined crimes; "accessory to torture" found sufficient.

- *Kanja Sandy v Secretary of State for the Home Department* **[2023] EWHC 640 (Admin)**: Claimant was aide-de-camp to Sierra Leone coup leader Johnny Paul Koroma (indicted by the Special Court for Sierra Leone). The court confirmed exclusion from refugee protection under Art.1F(a) given the claimant's proximity to a regime that committed war crimes, even if personal direct participation was not proven at the highest level. **Ratio**: Senior proximity to a regime committing atrocities can ground Art.1F(a) exclusion even without direct perpetration.

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## 5. SELF-DETERMINATION AND DECOLONISATION

- *Lysongo v FCO* **[2018] EWHC 2955 (QB)**: The claimant sought declarations that British Southern Cameroons' 1961 union with Cameroon was unlawful under international law / UN resolutions; that BSC "remains part of the United Kingdom." The court struck out the claim. **Ratio**: UK domestic courts cannot adjudicate whether historical decolonisation decisions violated international self-determination norms; these are not justiciable as private rights in domestic courts.

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## SUMMARY TABLE OF KEY RETRIEVED CASES

| Case | Citation | Core Principle |
|------|----------|---------------|
| Benkharbouche v SSFCA | [2017] UKSC 62 | SIA s.4(2)(a) disapplied — ECHR Art.6 / EU Charter Art.47 override blanket state immunity bar on employment claims |
| SerVaas v Rafidian Bank | [2012] UKSC 40 | SIA s.13(4) "commercial purposes" — property's current/intended use, not underlying transaction |
| Argentum Exploration v South Africa | [2024] UKSC 16 | Silver for coinage = sovereign purpose; SIA immunity applies despite commercial shipment |
| Harb v HRH Prince Abdul Aziz | [2014] EWHC Ch 1807 | Pinochet principles restated: former HoS — no immunity for torture (ratione materiae limited to lawful official acts) |
| Spain v Infrastructure Services | [2026] UKSC 9 | ICSID Convention overrides SIA immunity on registration of investment awards |
| Border Timbers v Zimbabwe | [2024] EWHC 58 (Comm) | SIA exceptions apply to ICSID land-expropriation enforcement |
| CC/Devas v India | [2025] EWHC 964 (Comm) | NYC ratification = submission to jurisdiction under SIA s.2(2) |
| PAO Tatneft v Ukraine | [2018] EWHC 1797 (Comm) | BIT arbitration clause = SIA s.9 immunity waiver |
| Hulley v Russian Federation | [2023] EWHC 2704 (Comm) | Issue estoppel applies in investment award enforcement |
| Kingdom of Spain v L Lorenzo | [2023] EAT 153 | VCDR Art.31 diplomatic immunity does not extend to State; SIA s.4(2)(a) disapplied |
| Lysongo v FCO | [2018] EWHC 2955 (QB) | UK courts cannot adjudicate inter-state international law violations as private rights |
| AB v SSHD | [2020] UKUT 268 (IAC) | Art.1F(a) — accessory to torture sufficient for refugee exclusion |
| Kanja Sandy v SSHD | [2023] EWHC 640 (Admin) | Senior proximity to atrocity-committing regime grounds Art.1F(a) exclusion |