Cover page
Title page
Table of Contents
Introduction
Introduction
Rules governing the use of force are considered essential for maintaining global
order and stability. International law is the main source of rules that govern relations
between states and other international actors, aiming to regulate peace and conflict
(Shaw, 2017). These rules preserve international order by limiting the use of force
and ensuring wars that do take place, follow humanitarian and legal boundaries.
The controversy surrounding the Russia-Ukraine war has raised serious questions
regarding the authority and effectiveness of international law in regulating armed
conflict. At the centre of the controversy lies the issue of whether Russia’s actions in
this war are consistent with the legal principles of international law.
This report will analyse both the initiation of the conflict and Russia’s conduct during
hostilities and argues that Russia’s war against Ukraine is unlawful under
international law.
The analysis will proceed in several stages. It will start by discussing the main laws
governing war, beginning with the rules that apply when starting a war, thereafter
moving on to the ones that regulate conduct during a war. It will then consider how
these frameworks apply in the case of the war between Russia and Ukraine. Finally,
the report will reflect on what this means for the credibility and enforcement of
international law.
Core contents
Jus ad bellum: laws on entering war.
Modern international law is built around the idea that states are not allowed to use
armed force. This is mainly supported by The United Nation Charter, which states
“threat or use of force against the territorial integrity or political independence of any
state” is prohibited (UN Charter, 1945, Article 2(4)). This is considered the absolute
norm for international law, which binds just all states (Shaw, 2017:45). There are only
2 exceptions to this rule, this includes being authorised by the United Nations
Security Council to use force if you are within your legal rights of self-defence in
response to an attack (UN Charter, 1945, Article 51).
The International Court of Justice has shown, on multiple occasions, that these
exceptions are not rewarded easily. The Court has ruled that a state cant truly be
claiming to use self-defence unless there has been an armed attack and the
retaliation was both necessary and proportionate (Nicaragua v United states, ICJ,
1986). In addition, preventive or pre-emptive cases of self-defence or the use of
humanitarian reasoning, without Security council authorisation, have not been
accepted as valid or lawful under international law (Bordelon, 2013:117).
Jus in bello: Laws on conduct of war
After a war has already started, the focus shifts from the lawfulness of the origin of
said war to the means and methods through which the war is being conducted,
regardless of the legality of the conflict’s origins. This new focus is due to the
international humanitarian law, or jus in bello. The key sources to these rules of
conduct are the Geneva Conventions of 1949 as well as their additional protocols.
These treaties ended up establishing the detailed rules and limits on certain
weaponry and war tactics with the intent of protecting civilians, and other parties
involved in wars (Dinstein, 2016: 89; ICRC, 1987).
The foundations of jus in bello lie in distinction, proportionality, and military necessity.
Distinction requires all participating parties in a conflict to distinguish between
civilians and other participating parties, targeting only the latter if for legitimate
military objectives. Proportionality means prohibiting attacks when the expected to
be harm done to civilians is not fairly proportionate to the gains received for military
purposes. Military necessity refers to limiting force to what is absolutely required to
achieve their military goals (Protocol I Additional to the Geneva Conventions, 1977,
Articles 48, 51, 52). These principles are implemented to mitigate human suffrage
and keep an essential minimum to the humanity present in war. For example, the
bombardment of cities without reason is not allowed and reflects distinction, while
proportionality is reflected through the prohibition of excessive collateral damage.
The International Committee of the Red Cross has consistently emphasised that
these rules are binding on all parties to conflict, regardless of whether they recognise
each other as legitimate belligerents (ICRC, 1987).
Jus ad Bellum applied to Russia
On 24 February 2022 Russia launched a full-scale invasion on Ukraine, moving
troops across the border and becoming hostile immediately. According to UNGA
Resolution ES-11/1 (2022), Russia’s invasion of Ukraine was condemned as a
violation of the UN Charter. Prior to this, Russia had recognised Donetsk and
Luhansk – two self-proclaimed people’s republics – as independent states of
Ukraine. They justified their use of force as self-defence, alleging that they had been
attacked previously by these entities. This, however, was not recognised under the
international law as Article 51 of the UN Charter only allows self-defence when an
armed attack occurs against a state (UN Charter, 1945, Article 51). Seeing as
Donetsk and Luhansk were not internationally recognised as sovereign states,
Russia’s justification was not considered valid (Gray, 2018)
Russia’s second justification was that it’s hostility was necessary to protect Russianspeaking populations in eastern Ukraine, who Russia had alleged were victims of
persecution and genocide by the Ukrainian government. Russia had said this to
frame their invasion as a rightful act of humanitarian intervention, however, even this
reasoning could not justify their use of force. The International Court of Justice has
clarified that such justifications do not permit military action with approval from the
UN Security Council (ICJ, 1986). Russia’s claims have even been shown to be false
after thorough investigations from the Organization for Security and Co-operation in
Europe (OSCE) where no evidence was found regarding the persecution or
genocide of Russian citizens in eastern Ukraine prior to the invasion (OSCE, 2022).
The final justification Russia had provided for its actions was that The North Atlantic
Treaty Organization (NATO) has expanded eastward, improving the ties between the
West and Ukraine. This had posed an existential threat, according to Russian
officials and had pushed them to demand a neutral status from Ukraine, which would
mean abandoning their connections with NATO. The requirement for self-defence, as
established by the ICJ, is that self-defence can only be justified if the threat is a
current or imminent armed attack (Dinstein, 2016). This would mean that Russia’s
claims had again not met the necessary requirements to claim self-defence.
Clearly, Russia’s justifications for the invasion do not fall within the requirements for
their use of force to be legally legitimised.
Jus in bello applied to Russia.
After the war had started, Russia’s conduct had raised some serious concerns under
jus in bello. For instance, there were many reports of Russia bombarding civilian
areas indiscriminately, as well as attacks on schools, hospitals, and residential
buildings (Human rights watch, 2022). These actions violate the principle of
distinction, which forces militants to distinguish between civilians and other militants,
as well as to only target lawful military objectives.(Geneva Conventions, 1949,
Articles 48 and 51)
The principle of proportionality is also implicated by Russia, as evidence from
satellites and other investigations have shown bombardments in areas where there
are no valid military target. The result being a high number of civilian casualties for a
small military advantage (United Nations Human Rights Council, 2022).
Proportionality prohibits attacks where the expected harm to civilians is excessive
when compared to the potential military advantage that may be received.
Russia has also failed to comply with the final principle, military necessity. Russia
had targeted areas with critical civilian infrastructure without any military purpose in
mind. The resulting damage done to water supplies, hospitals, and electricity
networks served toward their ulterior motives to coerce the Ukrainian population.
This directly contradicts the principle of military necessity, which restrict the use of
force to what is absolutely required to achieve military goals, and is explicitly
prohibited under internation humanitarian law (Protocol I Additional to the Geneva
Conventions, 1977, Article 52; McDonald, 2021: 55).
In summary, Russia’s actions during the war in Ukraine breaches the principles of
distinction, proportionality, and military necessity and are thus unlawful under jus in
bello.
Implications for the credibility and enforcement of international law
The war between Russia and Ukraine has brought to light a large discrepancy
between the international laws and the enforcement thereof. The UN Charter and
Geneva Conventions clearly prohibit the aforementioned actions of Russia within
their war with Ukraine. Russia has continued their actions through significant
amounts of backlash and condemnation, most notably from the UN General
Assembly Resolution ES -11/1 (2022).
This is primarily due to the real limitations of enforcement of international law. The
UN Security Council is the main source for taking action and enforcing the
international laws, and yet it has been widely criticised for not being able to respond
to Russia. Secretary-General Antonio Guterres notes that their inaction over the
subject has “undermined it’s authority” (Guterres, 2024:7).
Ukraine has made strong effort to seek accountability, as they have challenged
Russia’s misuse of the Genocide Convention before the International Court of
Justice. The International Criminal Court has also started multiple investigations into
alleged war crimes that Russia may have committed, some of which are still
currently underway. However, these actions have not halted the conflict, and are
merely signalling that Russia’s violations will not go uncontested and that
international law should not go unchecked as it has been throughout the conflict.
This case demonstrates that although Russia’s actions may be illegal and
international law remains important for defining legality, the capabilities to truly inhibit
these illegal action may not always be present.
Conclusion
An analysis of Russia’s war against Ukraine clearly shows that the war is illegal
under international law. Under jus ad bellum, Russia’s justifications – their claims of
self-defence, protection of Russian-speaking populations, or pre-emptive measures
against NATO expansion – fail to meet their criteria. Thus, leading to the conclusion
that their invasion was unlawful.
Under jus in bello, Russia’s conduct violates all of the key principles of international
humanitarian law – their indiscriminate attacks on civilians, the targeting of civilian
infrastructure, and the disproportionate use of force without proper justification.
According to the Geneva Conventions, this would render the actions of Russia
during the war unlawful.
While international law remains essential for defining legality and holding states
accountable, the war also highlights limitations in enforcement. The inability to
enforce the international law does not imply that Russia’s actions are justified, only
the incompetence of those entrusted with holding Russia accountable. Russia’s
actions, both in initiating and conducting the war, clearly breach international legal
norms, reaffirming the conflict’s illegality.
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