I. Background of the Sudan v. UAE case

Sudan instituted proceedings against the UAE at the ICJ, alleging that the UAE provided support to rebel groups implicated in genocidal acts during the Darfur conflict.Footnote ⁴ Sudan accused the UAE of complicity in genocide through material assistance to, and control over, armed factions engaged in systematic attacks against civilian populations. The UAE, however, had lodged a reservation to Article IX of the Genocide Convention upon its accession, which permits states to exclude the compulsory jurisdiction of the ICJ over disputes arising under the treaty.Footnote ⁵ This reservation formed the crux of the jurisdictional objection raised by the UAE.

The ICJ was thus tasked with determining whether the UAE’s reservation precluded the Court’s jurisdiction. This issue arose against the backdrop of the Court’s prior genocide-related jurisprudence, especially the landmark Bosnia v. Serbia case, which clarified the scope of jurisdiction and the interplay between treaty obligations and state sovereignty.Footnote ⁶ The Sudan v. UAE case introduces novel questions regarding the validity and effect of reservations under the Genocide Convention, the threshold for jurisdiction, and the evidentiary standards applicable in requests for provisional measures.Footnote ⁷

II. Legal framework: Article IX and state responsibility under the Genocide Convention

Article IX of the Genocide Convention provides the jurisdictional basis for the ICJ to adjudicate disputes arising from the interpretation, application, or fulfilment of the Convention.Footnote ⁸ However, Article XII of the Convention permits states to formulate reservations to its provisions, including jurisdictional clauses, thereby enabling them to exclude or limit compulsory dispute settlement.Footnote ⁹ This dual structure creates inherent tensions between the principle of state sovereignty and the imperative to prevent and punish genocide as an international crime of jus cogens status.Footnote ¹⁰

The UAE’s reservation specifically excludes the ICJ’s compulsory jurisdiction under Article IX, which raises the question of the extent to which such a reservation can be invoked without undermining the Convention’s object and purpose.Footnote ¹¹ Under international law, reservations that conflict with the essential purpose of a treaty may be considered invalid or impermissible.Footnote ¹² The legal framework governing state responsibility under the Convention includes both direct perpetration of genocide and complicity, each carrying implications for jurisdictional analysis.Footnote ¹³

Next section examines these legal principles with emphasis on the balance between respecting state consent in international adjudication and ensuring effective enforcement of the fundamental human rights norms embodied in the Genocide Convention.Footnote ¹⁴

III. The UAE’s reservation to Article IX: legal validity and effect

The UAE formulated a reservation to Article IX of the Genocide Convention, explicitly excluding the ICJ’s compulsory jurisdiction over disputes arising from the Convention.Footnote ¹⁵ The ICJ, in its ruling, accepted this reservation as valid, thereby precluding its jurisdiction in Sudan v. UAE.Footnote ¹⁶ This acceptance has sparked scholarly debate, given the tension between such reservations and the non-derogable obligations under the Genocide Convention, which many argue enjoy jus cogens status.Footnote ¹⁷ The Court’s reasoning relied heavily on the principle of pacta sunt servanda and state sovereignty, emphasising that reservations permitted under Article XII must be respected unless manifestly incompatible with the object and purpose of the treaty.Footnote ¹⁸ However, many legal scholars assert that reservations that limit dispute settlement mechanisms crucial for enforcing treaty obligations, particularly in the context of genocide prevention and punishment, may contravene the treaty’s essential purpose and international law principles.Footnote ¹⁹

Moreover, the doctrine of severability, which allows invalid parts of a reservation to be severed while preserving the state’s participation in the treaty, raises questions about whether the UAE’s reservation should have been partially invalidated.Footnote ²⁰ This section explores the legal validity and effect of the UAE’s reservation, assessing arguments for and against its enforceability, and the broader implications for international treaty law.

IV. Doctrinal debate on reservations to the Genocide Convention

The permissibility and implications of reservations to the Genocide Convention remain a matter of intense doctrinal debate.

Proponents of reservations argue that treaty law must preserve the sovereignty of states and encourage widespread participation. Under Articles 19 to 23 of the Vienna Convention on the Law of Treaties (VCLT), states are permitted to make reservations unless those reservations are prohibited or incompatible with the object and purpose of the treaty (pursuant to Article 19 of the VCLT). According to Murphy, such flexibility fosters broader adherence to multilateral instruments, and the test of permissibility must hinge on whether a reservation conflicts with the treaty’s object and purpose, not merely on its content.Footnote ²¹ Pellet further argues that pragmatic acceptance of reservations balances legal idealism with political reality, preventing the exclusion of states from vital human rights treaties.Footnote ²²

Critics of reservations, however, stress that treaties safeguarding jus cogens norms such as the prohibition of genocide require stricter standards. The 1951 ICJ Advisory Opinion on Reservations to the Genocide Convention acknowledged the Convention’s unique nature and emphasised that reservations inconsistent with its object and purpose are impermissible.Footnote ²³ Tams contends that where the Convention aims to protect the most fundamental values of the international community, reservations – especially those restricting accountability – must be carefully scrutinised or outright rejected.Footnote ²⁴

Particularly contentious are reservations to Article IX, which confers jurisdiction on the ICJ. Kohen highlights that allowing states to opt out of judicial oversight defeats the Convention’s enforceability.Footnote ²⁵ Sudan’s claim against the UAE emphasised that reservations that nullify dispute resolution mechanisms violate the Convention’s essence and undermine the collective commitment to punish genocide. Thus, while the ICJ’s decision in Sudan v. UAE may formally respect the principle of state consent, it has reignited debates about the legitimacy of reservations that undercut core obligations. As per the ICJ’s 1951 Advisory Opinion, any such reservation must be deemed invalid if it contradicts the Convention’s object and purpose – a principle whose enforcement remains elusive.

V. The ICJ’s jurisdiction and the precedents set in Bosnia v. Serbia and The Gambia v. Myanmar

The jurisprudence of the ICJ in genocide-related disputes notably includes the landmark cases of Bosnia and Herzegovina v. Serbia and Montenegro and The Gambia v. Myanmar, both of which have shaped the Court’s approach to jurisdiction and state responsibility under the Genocide Convention.

In Bosnia v. Serbia, the Court affirmed its jurisdiction despite Serbia’s objections, holding that the Genocide Convention creates obligations erga omnes partes and that the dispute settlement provisions are integral to the Convention’s object and purpose.Footnote ²⁶ The Court emphasised that reservations cannot be invoked to undermine the fundamental obligations to prevent and punish genocide, underscoring the non-derogable nature of these commitments.Footnote ²⁷ This case set a precedent reinforcing that state parties cannot evade responsibility through jurisdictional reservations incompatible with the Convention.Footnote ²⁸

By contrast, in The Gambia v. Myanmar, the ICJ issued provisional measures ordering Myanmar to prevent genocide against the Rohingya population.Footnote ²⁹ The Court applied a plausibility standard for jurisdiction and evidentiary thresholds, which demonstrated a willingness to engage proactively with urgent human rights concerns, including genocide allegations.Footnote ³⁰ The Court’s analysis in The Gambia v. Myanmar reflected an evolving standard for assessing the admissibility of claims and the application of provisional measures in genocide cases.Footnote ³¹ In Sudan v. UAE, however, the Court diverged from these precedents by upholding the UAE’s reservation and denying jurisdiction.Footnote ³² This inconsistency raises critical questions about the coherence of the ICJ’s genocide jurisprudence and its implications for enforcing the Genocide Convention.Footnote ³³ The current case thus highlights the need for clearer and more consistent legal standards governing the effect of reservations on jurisdiction in genocide disputes.Footnote ³⁴

The difference in approach between The Gambia v. Myanmar and Sudan v. UAE can largely be attributed to the existence of a reservation. Myanmar did not enter any reservation to Article IX of the Genocide Convention, thereby allowing the ICJ to exercise jurisdiction without further consent. Conversely, the UAE made a clear reservation to Article IX upon accession in 2021. This distinction is pivotal. In The Gambia v. Myanmar, the Court rightly underscored the erga omnes nature of obligations under the Convention. However, in Sudan v. UAE, the Court failed to reconcile the universal character of these obligations with the implications of reservations, reflecting an inconsistency in its jurisprudence.

VI. Analysis on the validity of Article IX reservations under the Genocide Convention

In light of the 1951 Reservations to the Genocide Convention Advisory Opinion, the ICJ made clear that the permissibility of any reservation depends on its compatibility with the object and purpose of the treaty.Footnote ³⁵

Consequently, a reservation that seeks to exclude the jurisdiction of the Court under Article IX – while simultaneously accepting obligations to prevent and punish genocide—appears conceptually inconsistent. A state cannot, in principle, claim to accept the duty to prevent genocide yet deny the very judicial mechanism established to ensure compliance with that duty.Footnote ³⁶

Although the Court has developed a certain jurisprudence constante suggesting tolerance towards Article IX reservations, this practice should not be mistaken for an immutable rule of law. In several instances, the ICJ has, either explicitly or implicitly, bypassed reservations when the object and purpose of a treaty demanded substantive adjudication, particularly in cases where fundamental human rights norms were at stake.Footnote ³⁷

Therefore, the mere existence of a long-standing pattern of acceptance does not necessarily validate the legality of such reservations. The argument that reservations to Article IX are necessary to secure broader participation in the Convention is normatively appealing, yet participation without effective accountability amounts to little more than a formal exercise devoid of real legal consequence.Footnote ³⁸

VII. The alleged genocide and the role of the UAE: complicity, control, and attribution

The allegations against the UAE in Sudan v. UAE revolve around its purported support to armed groups involved in genocidal acts in Darfur. International criminal law distinguishes between direct perpetration and complicity, with complicity requiring proof of knowledge and substantial contribution to the commission of genocide.Footnote ³⁹ The principle of state responsibility extends to acts of aiding or assisting other actors in breaches of the Genocide Convention, provided such aid is given with intent and effective control.Footnote ⁴⁰ The International Criminal Court (ICC) has elaborated on these standards, notably in its jurisprudence concerning the Darfur situation, underscoring the importance of attributing conduct to states based on effective control over non-state actors.Footnote ⁴¹ In the present case, the evidentiary burden lies in demonstrating that the UAE exercised sufficient control or encouragement over the alleged perpetrators to establish complicity.Footnote ⁴² The ICJ’s approach at the preliminary jurisdictional stage, however, typically involves a lower threshold focused on the plausibility of claims rather than proof beyond reasonable doubt.Footnote ⁴³ The Court’s handling of factual allegations in Sudan v. UAE, including the scope of evidence accepted for provisional measures, reflects tensions between the need for judicial caution and the urgency of preventing further harm.Footnote ⁴⁴

VIII. Provisional measures and the threshold of plausibility

Provisional measures serve as urgent judicial remedies to prevent irreparable harm pending the final adjudication of a case. In genocide disputes, their importance is paramount due to the potential for ongoing violations of fundamental human rights and mass atrocities.Footnote ⁴⁵ The ICJ’s jurisprudence, notably in The Gambia v. Myanmar, has underscored the necessity for a plausible legal and factual basis to warrant the granting of such measures.Footnote ⁴⁶ In Sudan v. UAE, the Court applied a stringent plausibility threshold, requiring credible evidence that the applicant’s claims meet a certain threshold of likelihood.Footnote ⁴⁷ This approach has been critiqued for imposing evidentiary demands that may hinder effective protection, especially when facts are contested or obscured in conflict zones.Footnote ⁴⁸ The Court’s reasoning must be understood alongside procedural rules of the ICC, which balance the need for prompt action with safeguards against misuse.Footnote ⁴⁹

Furthermore, UN Human Rights Council resolutions relating to Darfur emphasise the international community’s responsibility to act decisively, reflecting normative expectations that should inform judicial discretion regarding provisional measures .Footnote ⁵⁰ This nexus between legal standards and political imperatives highlights the complex role of the ICJ in genocide cases.

IX. Critical evaluation of the ICJ’s ruling on jurisdiction

The ICJ’s ruling in Sudan v. UAE reveals significant tensions between state sovereignty and the imperative to prevent genocide through effective adjudication. By upholding the UAE’s reservation to Article IX of the Genocide Convention, the Court effectively limited its jurisdiction, raising questions about the enforceability of treaty obligations under jus cogens norms.Footnote ⁵¹ Scholars such as Mendelson and Cassese argue that reservations that undermine core treaty objectives, especially in human rights and genocide law, should be considered invalid or at least partially severable.Footnote ⁵² This perspective emphasises the primacy of the Convention’s object and purpose over unilateral state reservations. The Court’s acceptance of the reservation may thus represent an overly deferential approach to state consent, potentially weakening international legal mechanisms designed to combat impunity.Footnote ⁵³ Moreover, the ICJ’s jurisprudence in Bosnia v. Serbia established that jurisdiction should not be easily negated by reservations that conflict with jus cogens.Footnote ⁵⁴ The divergence in Sudan v. UAE suggests a need for doctrinal evolution to harmonise the Court’s approach with broader principles of international criminal law and state responsibility.Footnote ⁵⁵ Alternative interpretative frameworks, including the doctrine of partial invalidity of reservations and principles of systemic integration, provide potential pathways for strengthening jurisdictional competence without infringing state sovereignty unduly.Footnote ⁵⁶ This evolution is critical for ensuring that genocide disputes are effectively adjudicated and that treaty obligations retain their normative force. See below table:

Parties’ Arguments and the ICJ’s Position at a Glance

X. The broader implications for future reservations under human rights and humanitarian law treaties

The ICJ’s judgement in Sudan v. UAE not only affects the interpretation of Article IX of the Genocide Convention but also raises broader implications for the permissibility and legal consequences of reservations under multilateral human rights and humanitarian law treaties. By allowing a state to make a reservation that effectively neutralises a core provision of a treaty while simultaneously limiting judicial review through procedural objections, the Court risks encouraging a fragmented and strategic approach to treaty participation. This outcome is particularly concerning in legal regimes where universality and integrity are paramount, such as the prohibition of genocide and other jus cogens norms. The Court’s reluctance to engage substantively with the effects of the UAE’s reservation, and its choice to frame Sudan’s objection as a matter of consent and jurisdiction rather than the legal validity of the reservation, signals a shift away from the Vienna Convention’s object-and-purpose test (Articles 19–23) as a controlling framework. While the Genocide Convention predates the VCLT, the interpretive principle that reservations are incompatible with a treaty’s object and purpose are invalid has become a cornerstone of treaty law. This is especially true for human rights instruments where individual rights are at stake.Footnote ⁵⁷ This raises a potential tension with prior jurisprudence, including the Court’s influential 1951 Advisory Opinion on Reservations to the Genocide ConventionFootnote ⁵⁸ and subsequent cases like Bosnia v. Serbia Footnote ⁵⁹ and Croatia v. Serbia,Footnote ⁶⁰ where the ICJ showed willingness to evaluate the substantive impact of states’ reservations. By treating Sudan’s legal action as a procedural challenge rather than a substantive critique of the UAE’s reservation, the Sudan v. UAE judgement may embolden future states to shield problematic reservations from scrutiny, undermining the consistency and enforceability of human rights treaties. Moreover, the judgement could weaken mechanisms for accountability under other treaties with compulsory dispute resolution clauses such as the Convention against TortureFootnote ⁶¹ or the International Convention on the Elimination of All Forms of Racial DiscriminationFootnote ⁶² by incentivising states to enter reservations framed in a way that denies the jurisdiction of international courts while maintaining nominal treaty participation. This threatens both the effet utile of these treaties and the broader goals of international cooperation in addressing mass atrocities and systemic violations.