Home > Publications > Commentary > International law after the war in Ukraine: The crumbling cascade

International law after the war in Ukraine: The crumbling cascade

Image of protest against Ukraine War in the US
Katarína Šipulová

Katarína Šipulová

A fellow of the Oxford Global Society and Head of the Judicial Studies Institute, Masaryk University

Share this post

Share on facebook
Share on twitter
Share on linkedin
Share on email

The views expressed are solely those of the author (s) and not of Oxford Global Society.

This article discusses the core challenges the Russian invasion posited for international law and explores the ideas of reforming the veto system of UN Security Council. It can be read together with a linked article: International law after the war of Ukraine: Towards the post-bellum accountability, which advances ideas on options that international law provide to prosecute the invasion and war crimes committed in Ukraine.

Since the beginning of the war in Ukraine, some commentators (here or here) have noted that although Putin gravely violated the UN Charter, he did not challenge the legitimacy of the non-aggression principle, or of the international law as such. Instead, Putin weaponised international law rhetoric when he tried to justify his invasion with claims of alleged ethnic genocide in Ukraine. The botched legal interpretation was quickly refuted by both the International Court of Justice and the European Court of Human Rights which ordered Russia immediately to cease all military activities in Ukraine. The mocking misuse of legal language is neither new nor surprising, but it prompts us to contemplate the repercussions of the Russian invasion on the quality, effectiveness and enforcement of the international law.

The whole system of the United Nations is built on the prohibition of the use of force and comprises a set of political, economic and legal tools aimed to guarantee member states’ compliance. On 24 February 2022, part of this system crumbled, spurring debates on how to re-construct it.

As I argue below, the critical challenge of the war in Ukraine is not that international law lacks clarity or that it fails to recognise crimes committed in Ukraine. The major issue to address is the constraints limiting compliance with and the enforcement of international law. 

The Ius ad Bellum and Ius in Bello of International law

One of the questions triggered by the Russian invasion and the mounting reports of atrocities occurring in Ukraine is what leverage can we find in international law? Did Russia not violate the core principles of international law and its commitments to the UN Charter? Should we not prosecute the horrible crimes we saw in Bucha? Should we not hold to account Putin and other orchestrators of the violation of Ukraine’s sovereignty, nation and humanity?

Generally, there are two core dimensions to how the international legal order is responding to the war: the first is the examination of whether the reason behind the use of force is a just one (this is what we call the ius ad bellum). The ius ad bellum arguments can be found directly in the UN Charter, which is built on the general prohibition of the use of force. Article 1.1 of the UN Charter states that one of the purposes of the UN is:

To maintain international peace and security, and to that end: to take effective collective measures for the prevention and removal of threats to the peace, and for the suppression of acts of aggression or other breaches of the peace, and to bring about by peaceful means, and in conformity with the principles of justice and international law, adjustment or settlement of international disputes or situations which might lead to a breach of the peace”.

Article 2.4 furthermore binds the member states to “refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state…”. There are only three exceptions to this rule: self-defence, collective self-defence or authorised action by the Security Council. These exceptions build on the commitment of UN member states to protect populations from genocide, war crimes or crimes against humanity by an appropriate use of diplomatic or humanitarian means (Chapter VI and VII of the UN Chapter). Typically, the authorised action responding to grave violations of human rights would materialise as a peace-keeping mission, humanitarian intervention or a responsibility to protect.

The second dimension focuses on how the war is conducted (the ius in bello). Irrespective of whether the intervention is just and legal, the ius in bello observes additional requirements regarding the treatment of civilians, prisoners of war, wounded soldiers and detainees, and prohibits the use of certain types of weapons aimed at civilian targets. These principles form the mass of humanitarian law, contained first and foremost in four Geneva Conventions. Humanitarian law is, however, reflected in many other treaties and documents, including the Nuremberg principles, statutes and case law of International Court of Justice, ad hoc international tribunals and, most importantly, in the Rome Statute of the permanent International Criminal Court (ICC). The modernisation of military equipment, with increased precision and ability to target military objects exclusively, fosters the validity of humanitarian law and precludes pragmatic justifications of civilian victims. The law is no longer silent during the war. In fact, research suggest that modern wars have led to a decrease in unnecessary victims, with approx. 1 in 5 wars resulting in war crimes. The reports of human rights atrocities from Ukraine demonstrate this quite well – the mass graves in Bucha or sexual violence against Ukrainian women are by no means inevitable side-effects of the war. These are deliberate actions of the Russian army that underline Putin’s rhetoric denying the cultural, political and human existence of the Ukrainian nation.

The magnitude of these questions increases when we look upon the architecture of the international system that is, at least formally, committed to values of peace and human rights protection. The world has never been more committed to human rights protection than it is today, when countries, both democratic and non-democratic, are bound by a plethora of international treaties and conventions. For decades now we have believed that the justice cascade and the complex system of international criminal law, including courts and tribunals, will have sufficient deterrent effect to reduce the propensity of world leaders to engage in aggressive wars and to commit atrocities. Russia itself has been a member of several universal and regional human rights regimes, albeit with a questionable level of compliance. Since its invasion of Ukraine, Russia’s membership in the UN Human Rights Council has been suspended and the country has been expelled from the Council of Europe, both steps generally condoned by law experts. The United States, Europe and other allies have imposed on Russia economic sanctions of so far unprecedented magnitude, although with only lukewarm reaction to a potential embargo on imports of Russian oil and gas, the main source of Putin’s ability to continue financing the war.

Reforming the Security Council ‘s veto system ?

A deeper and more worrying effect of the Russian invasion, however, is the credibility of the United Nations system and of its commitment to peace, security and human rights protection. Only UN imposed sanctions, diplomatic, economic, or military, can create a legal obligation on all countries to cooperate and refrain from further support of Russia. Similarly, the support of the Security Council is also inevitable for the effective enforcement of legal prosecutions of crimes committed in Ukraine, since only the Security Council has the authority to force third countries to cooperate and assist international courts and tribunals in the prosecution and extradition of war criminals.

It is important to repeat that the UN Charter does recognise the obligation of the international community to act in order to prevent human rights violations. In contrast to how Putin keeps interpreting the legitimacy or legality of any eventual military engagement by other countries in Ukraine, the duty to intervene against the use of force is the backbone of the UN’s collective security system. The stalling of the international community does not follow from the lack of a legal framework, but from the inherent limits of the structure of the international order: First, the paralysis of the Security Council due to the veto power held by permanent members (including Russia) and, second, the revived threats of mutually assured destruction and a potential nuclear war. We have for decades known but ignored these limits of the international order. The Security Council is effective in sanctioning only those conflicts that are not of major interest for the five veto-power-holding states.

The obvious question is how one moves away from this institutional gridlock. President Zelensky’s call for a reform of the UN SC veto system is fertilising long-existing debates on the reform of the use of veto power inside the UN Security Council.

Just briefly to summarise: the UN Security Council consists of 15 members, 10 elected and 5 permanent members holding a veto power (France, China, the Russian Federation, the United Kingdom and the United States). In order to maintain or restore international peace (one of the guiding principles of the UN Charter, Article 1), the Security Council can take various actions, including mandatory sanctions (Article 41) or the use of armed force. Since 1966 the SC has imposed 30 sanction regimes, but also faced considerable backlash for vetoing actions during the conflicts in Georgia, Syria or Crimea (to mention just the most recent events).  

Samuel Moyn and André Nollkaemper recently aptly summarized that the reform of the veto-power regime is not merely an issue of common sense, but a question of the credibility of international criminal law: which will remain undermined while some countries, through their veto power in the Security Council, have an unlimited number of get-off-free cards enabling them to violate norms of international law. Although the structure of the UN system materializes the logic of the balance of powers, it also inherently creates an imbalance between the great powers and the rest of the UN members and introduced an informal exception to the ius cogens (i.e. peremptory) norm of the prohibition of the use of force. With the full recognition that abolition of the veto power might impair the balancing function of the Security Council, there are several proposals for reforming the system that are worth considering.

The first scenario for reforming the current system would be to establish the clear illegality of vetoing actions of the SC which are related to the violation of ius congens norms (as proposed by Charles Jalloh here). In other words, vetoing a reaction to the violation of core principles of international commitments, such as an illegal use of force or the commission of war crimes, not only by the perpetrator but by any other SC permanent member, would be considered illegal (potentially even as itself violating international law). The foundation for the illegality of a veto in relation to ius cogens violations can be found, for example, in Article 41.2 of the International Law Committee’s Articles on State Responsibility for Wrongful Acts. Doctrinally, the illegality of a veto in such situations would push the UN Charter system towards constitutionalisation; however, it would most probably also be met with reluctance on the part of at least some SC members.

Another scenario would be the introduction of limits to the veto power: compared to the first scenario, veto in certain situations would be not illegal or null, but technically impossible. André Nollkaemper discusses two alternative versions currently on the table: an obligation to abstain from vetoing decisions under Chapter VI when the superpower itself is a party to the dispute, or the less strict voluntary agreement of the permanent members to refrain from using the veto in situations of mass atrocities. Both scenarios are discussed in considerable detail here. Suffice it to say that the first path brings the UN system actually closer to a standard sanctioning mechanism. The nemo iudes in sua causa is present in the majority of regional organisations – such as e.g. the sanctioning of violations of  the core principles of the European Union under Article 7 of Treaty on European Union. Two follow-up questions remain to be solved: how to formalise such an amendment of the UN Charter (or its interpretation) and how to monitor its observance. As many commentators have already suggested, limitation of the use of veto should not be subjected to a vote by the Security Council as that might, once again, lead the organisation into gridlock. Instead, an option worth considering would be the incorporation of a limitation directly into veto procedure in the UN Charter.

As much as debates on restructuring the UN veto system might seem radical or even idealistic, the frequent violations of international law and legitimate use of force now magnified by the Russian invasion suggest that reliance on the standing system is just as idealistic and naïve. Perhaps the time has come to rebuild its credibility.  

“It is the very nature of things human that every act that has once made its appearance and has been recorded in the history of mankind stays with mankind as a potentiality long after its actuality has become a thing of the past. No punishment has ever possessed enough power of deterrence to prevent the commission of crimes. … It is essentially for this reason: that the unprecedented, once it has appeared, may become a precedent for the future, that all trials touching upon “crimes against humanity” must be judges according to a standard that is today still an “ideal”. ….Success or failure in dealing with the hitherto unprecedented can lie only in the extent to which this dealing may serve as a valid precedent on the road to international penal law.”

—Hannah Arendt, Eichmann in Jerusalem, 2014, p. 273