Felicitas Benziger, Dipl.-Jur. LLM University College London, MPhil/PhD Candidate at Middlesex University London

On February 24 2022, the world woke up to shocking news: Russia started its military invasion in Ukraine. World leaders were quick to rally and organise emergency meetings to plan the next strategic moves. In the international community, Putin’s move is unequivocally deemed a gross breach of international law (see for example, the UN Secretary General’s statement). Yet, Putin references international law in defending his actions.

Two main legal grounds can be discerned as being alluded to by Putin in his speech as justifications for the invasion.

First, Putin asserts that Russia’s military invasion is in compliance with Art. 51 of the UN Charter, which provides for the right of individual or collective self-defence in the case of an armed attack:

“In this regard, in accordance with Article 51 of Part 7 of the UN Charter, with the sanction of the Federation Council of Russia and in pursuance of the treaties of friendship and mutual assistance ratified by the Federal Assembly on 22 February this year with the Donetsk People’s Republic and the Luhansk People’s Republic, I decided to conduct a special military operation.”

and furthermore

“I repeat, our actions are self-defence against the threats posed to us and from an even greater disaster than what is happening today.”

Within that frame, he offers two possible grounds of justification. On the one hand, he maintains that Russia is acting in self-defence in face of a threat to itself. In a variation of this theme, Putin also refers to the republics of Donetsk and Luhansk which asked the Russian Federation for military assistance. It looks, thus, as if Putin is seeking to base his self-defence case on two pillars: firstly, that Russia needs to defend itself, secondly, that it is defending two other states.

With regards to Russian self-defence on its own behalf, while recognising that there is a lot of controversy concerning particular conditions of the right to self-defence (see Chris O’Meara, Necessity and Proportionality and the Right of Self-Defence in International Law (OUP 2021); see also here), according to established jurisprudence, two requirements must be fulfilled: that of necessity and that of proportionality (see the ICJ’s Nicaragua case at paras. 176, 194). Despite forming the core of the international right to self-defence, the two concepts of necessity and proportionality have not been conclusively defined in abstract legal terms, thus leaving room to a degree of uncertainty. The ICJ did, however, find that an armed attack is the conditio sine qua non for the right to self-defence to be triggered (Nicaragua, para. 237). As a matter of fact, this requirement is not fulfilled in the current situation. Instead, the OSCE report suggest the opposite, that breaches of the ceasefire agreement concerning Donetsk and Luhansk had been violated by Russian separatists. However, even assuming that there was an armed attack, the threshold for determining whether or not self-defence is necessary in legal terms is high – as the ICJ emphasised in Oil Platforms (para. 73): “(…) the requirement of international law that measures taken avowedly in self-defence must have been necessary for that purpose is strict and objective, leav[es] no room for any “measure of discretion”.” Furthermore, in Nicaragua it was established that “the State which is the victim of an armed attack (…) must form and declare the view that it has been (…) attacked. There is no rule in international law permitting a State to exercise the right of collective self-defence on the basis of its own assessment of the situation. Where collective self-defence is invoked, it is to be expected that the State for whose benefit this right is used will have declared itself to be the victim of an armed attack.” (para. 195). No such declaration was, however, issued by Russia on its own behalf. Instead, Putin merely refers to NATO’s alleged expansionism, which he categorises as

“ultimately a matter of life and death, a matter of our historical future as a people. And this is not an exaggeration: it is true. This is a real threat not just to our interests, but to the very existence of our state, its sovereignty.”

Furthermore, the requirement of proportionality was clearly violated, given the extent of Russia’s military invasion in Ukraine, which extends far beyond the separatist regions of Donetsk and Luhansk, whose statehood remains at issue at best (see also this recent post). In fact, Russia was the only UN member recognizing the statehood of the separatist regions, and the overwhelming response from the international community was rejection of any such notion.

With regards to an act of defence on behalf of the republics of Donetsk and Luhansk, similar issues arise, not least concerning the requirement of an armed attack declaration by a ‘State’ – Putin’s solitary recognition of the two republics does not fulfil the statehood requirement.

The second international legal ground implicitly referenced is that of a humanitarian intervention or even of the doctrine of the responsibility to protect (R2P). Putin implies this when he justifies the necessity of the military invasion with an alleged genocide that is said to have taken place on Ukrainian soil for eight years:

“Its [the military operation’s] goal is to protect people who have been subjected to bullying and genocide by the Kiev regime for eight years. And for this we will strive for the demilitarisation and denazification of Ukraine, as well as bringing to justice those who committed numerous, bloody crimes against civilians, including citizens of the Russian Federation.”

First, Russia’s allegations of a genocide in Ukraine are not based on any data or evidence. Second, humanitarian intervention or even the doctrine of the R2P cannot evade the prohibition of the use of force under Art. 2(4) of the UN Charter. The majority of international scholars and institutions, and almost all UN members, reject such a notion (similarly, this post). Needless to say, that the extent of Russia’s military activities Ukraine exceeds by far the extent necessary or even proportionate for any humanitarian purposes. Still unknown numbers of civilian casualties and large-scale air raids also affecting civilians will be something to be considered in that regard and further weaken the case for humanitarian intervention.

If one agrees that none of the international legal justifications raised by President Putin apply, what remains is considering what responsibility he might have to accept under international law. The Russian Federation is accountable within the framework of state responsibility, for a violation of Art. 2 (4) UN Charter and for committing an act of aggression. Furthermore, Putin seems to have committed a crime of aggression as defined in Arts. 5 and 8 bis of the Rome Statute of the International Criminal Court (ICC). As neither Urkaine or Russia are State Parties to the Rome Statute, the ICC cannot exert is jurisdiction on the crime of aggression. The Court can investigate acts of genocide, crimes against humanity or war crimes committed within the territory of Ukraine pursuant to the Ukranian declaration of 2015. Still, an analysis of the definition of aggression allows examining if such crime was perpetrated.

Paragraph (1) of Art. 8 bis ICC Statute reads:

“For the purpose of this Statute, “crime of aggression” means the planning, preparation, initiation or execution, by a person in a position effectively to exercise control over or to direct the political or military action of a State, of an act of aggression which, by its character, gravity and scale, constitutes a manifest violation of the Charter of the United Nations.”

There is no question that Putin not only initiated, but executed a military action against another state, which starkly contradicts the prohibition of the threat and use of force and the principle of territorial integrity of sovereign states provided in Art. 2 (4) UN Charter, thus constituting a manifest violation of the Charter. Furthermore, Putin used military force against Ukraine, thereby fulfilling the element of aggression as set out in Art. 8 bis (2) ICC Statute:

“For the purpose of paragraph 1, “act of aggression” means the use of armed force by a State against the sovereignty, territorial integrity or political independence of another State, or in any other manner inconsistent with the Charter of the United Nations.  Any of the following acts, regardless of a declaration of war, shall, in accordance with United Nations General Assembly resolution 3314 (XXIX) of 14 December 1974, qualify as an act of aggression:

“(a) The invasion or attack by the armed forces of a State of the territory of another State, or any military occupation, however temporary, resulting from such invasion or attack, or any annexation by the use of force of the territory of another State or part thereof”.

Concluding, no matter the canting ‘justifications’ brought forward in President Putin’s speech – even if one ignores obvious factual problems, such as  the genocide allegations – there is no justification in international law for the start of an armed attacked on Ukraine considering the remaining requirements for the doctrines of self-defence, humanitarian intervention or R2P. Instead, it is more likely that the Russian leader has perpetrated a crime of aggression under Art. 5 ICC Statute.