The role of international law in Ukraine’s fight against Russian aggression

  • May 11, 2022
  • Dr. Gaiane Nuridzhanian and Lee-Ann Conrod


On the morning of 24 February 2022, the world woke up to the shocking news that Russia was bombing Ukraine and that Russian troops were crossing the border into Ukraine. Russia attempted to justify its invasion of Ukraine by invoking the right to self-defence and claiming that atrocities were being committed against Russians and the Russian-speaking population in Ukraine. While a state’s right to use force in individual and collective self-defence is firmly established in international law,1 there exists no right to intervene by force into the territory of another state for humanitarian reasons without that state’s consent or authorization of the UN Security Council. In any event, Russia’s claims to self-defence and humanitarian intervention have no factual basis whatsoever. For this reason, Russia’s unlawful use of force against Ukraine was condemned as an act of aggression by the UN General Assembly on March 2, 2022.2

Since the start of this war, the world has seen overwhelming evidence of Russian forces committing war crimes, crimes against humanity and possibly even genocide3 against the civilian population in Ukraine.4

Why this war is happening

Witnessing the daily horrors of this war, many struggle to understand why it is happening. At the core of this war is Russian President Putin’s imperialistic ambitions, nostalgia for the Soviet Union and denial of the existence of Ukrainians as a separate nation and of Ukraine as a sovereign state.5 In this ideology, there is no place for an independent, democratic state of Ukraine that is free to determine its own future.

The role of international law

Ukraine is fighting Russian aggression on the battlefield as well as in court. In March 2022, Ukraine succeeded in obtaining provisional measures against Russia before the European Court of Human Rights (ECHR) and the International Court of Justice (ICJ). The ECHR indicated that Russia must refrain from military attacks against civilians and civilian objects and ensure unimpeded access of the civilian population to safe evacuation routes.6 The ICJ ordered Russia to immediately suspend its military operations in Ukraine.7 Russia has failed to comply with the measures.

The role of the International Criminal Court

The Rome Statute, adopted in 1998, created the world’s first permanent international criminal court. Since the International Criminal Court (ICC) opened in The Hague, the Netherlands in 2002, it has offered the international community the promise of deterrence and accountability for mass atrocities. The ICC is one forum that can ensure the perpetrators of the heinous crimes committed in Ukraine find justice.

Although Ukraine is not a State Party to the ICC, it has accepted the court’s jurisdiction to prosecute accusations of war crimes, crimes against humanity and genocide committed within its borders since February 2014 and onwards.8

On March 2, 2022, ICC Prosecutor Karim Khan, QC opened an investigation into the Situation in Ukraine based on a reasonable basis to believe that both alleged war crimes and crimes against humanity had been committed in Ukraine.9 The Prosecutor was able to proceed to the investigation stage without obtaining authorization from an ICC Pre-Trial Chamber thanks to an unprecedented move by 39 ICC State Parties, including Canada, who formally referred the Situation in Ukraine to the ICC.10 Since the start of the investigation, the ICC Prosecutor has repeatedly visited Ukraine,11 and his investigative team is reported to be already working in Ukraine to collect evidence of the alleged crimes.

In an interview on March 3, 2022, Khan said that if war crimes are found to have been committed in Ukraine, “his office would follow the evidence up the chain of command, to the highest levels of political and military office” and that “[a]nybody involved in conflict needs to realise they don’t have a licence to commit crimes.”12 Mindful of the fact that the war was still ongoing, Khan called for “restraint and strict adherence to the applicable rules of international humanitarian law.”13

While it may take some time for the ICC to issue arrest warrants and try war criminals from the war in Ukraine, the ICC investigation is also critically important now. It brings attention to the crimes that are being committed. Its voice on the international stage counters propaganda over Russia’s disingenuous “humanitarian” reasons for the invasion. The ICC investigation also demonstrates and reinforces the world’s willingness to hold perpetrators to account and ensures there will not be impunity for these international crimes. The act of investigating and naming what is happening in Ukraine is also extremely important for mobilizing further international support for Ukraine’s fight against the unlawful aggression.

The crime of aggression

The actions of the Russian leadership in planning, preparing, initiating and executing the war against Ukraine amount to the crime of aggression. The ICC is not competent to exercise its jurisdiction over the crime of aggression committed by Russian leadership in Ukraine because neither Ukraine nor Russia are parties to the Rome Statute. There are, however, other avenues for prosecuting this crime. First, Ukraine itself possesses jurisdiction to prosecute the crime of aggression according to its Criminal Code.14 Second, the possibility of establishing a special international tribunal for prosecuting the crime of aggression by Russian leadership is now being seriously considered.15

The hope for justice

Whatever the chosen pathway, neither the crime of aggression nor other atrocities committed in Ukraine can remain unpunished. Impunity will set a dangerous precedent for the future. Moreover, investigating and prosecuting these crimes may have an important deterrent effect in the ongoing war. Finally, Ukrainian resilience and ability to carry on the struggle for freedom and survival is sustained, among other things, by the belief that justice will prevail and those responsible for this aggressive war and the crimes committed during it will be held responsible. Justice must deliver.

What you can do

Stay informed.

Fight disinformation.

Donate at Ukraine Red Cross - Emergency appeal

Visit Real ways you can help Ukraine as a foreigner website

Do whatever you can.16


Dr. Gaiane Nuridzhanian works as a senior lecturer at National University of Kyiv-Mohyla Academy in Ukraine. She holds an LLM degree from University of Cambridge and a PhD degree in law from University College London. She has previously worked as a lawyer at the European Court of Human Rights and Council of Europe, and as a Visiting Legal Researcher at the ICC.


Lee-Ann Conrod works as a Federal Prosecutor at the Public Prosecution Service of Canada in Halifax, Nova Scotia. She graduated with a Juris Doctorate from UNB Law in 2010 and Dalhousie’s Schulich School of Law with her LLM in 2018. In 2019, she worked at the ICC as a Visiting Professional. Lee-Ann teaches part-time in the criminology department at Saint Mary’s University and is an adjudicator for the Province of Nova Scotia.

End Notes

1 Article 51 of the UN Charter

2 Aggression against Ukraine, UNGA Res A/RES/ES-11/1 (22 March 2022) (adopted by 141 votes to 5; 34 abstentions)

3 Declaration of the Verkhovna Rada of Ukraine ‘On the Genocide Committed by the Russian Federation in Ukraine’ (14 April 2022)

7 Allegations of Genocide under the Convention on the Prevention and Punishment of the Crime of Genocide (Ukraine v Russia), International Court of Justice, Order of 16 March 2022

8 Ukraine accepts ICC jurisdiction over alleged crimes committed since 20 February 2014 (8 September 2015). For definitions of each of these crimes – war crimes, crimes against humanity and genocide – see Articles 5 through 8 of the Rome Statute: RS-Eng.pdf (

10 Two more states joined the referral at a later stage. Statement of ICC Prosecutor, Karim A.A. Khan QC, on the Situation in Ukraine (11 March 2022)

14 See Article 437 of the Criminal Code of Ukraine