The International Criminal Court “is a kind of a sword of Damocles for those who admit a possibility of achieving political goals by committing mass murders, extermination and violating international law.” It is ironic that these were the sentiments expressed by the Russian delegation at a conference to review the statute of the Court in Kampala in 2010. This raises the question, what are war crimes and what are the consequences when they are committed? This article seeks to address the main legal challenges in responding to what is happening in Ukraine today.  It draws attention to the selective nature of international justice, and the problems in enforcing existing international law and holding those responsible for war crimes accountable.

War crimes evoke images of the targeting of civilians, especially women and children, the destruction of civilian property, the mistreatment of prisoners and detainees, sexual violence, and the displacement of populations. It is a term often cited by commentators to describe events that defy our sense of shared humanity and violate the principles enshrined in the laws governing the conduct of armed conflict. However, the death of civilians and the destruction of civilian objects do not always mean that a war crime has been committed; as the term implies, war crimes have a technical meaning and cover certain actions taken in the course of an armed conflict that violate the principles of international humanitarian law.  Collateral damage is the term used to describe the incidental death of civilians or damage to civilian objects owing to an otherwise lawful military action.

War crimes come under the general umbrella of the branch of international law known as international humanitarian law, sometimes referred to as the law of armed conflict. The primary aim of international humanitarian law is to establish limits to the means and methods of armed conflict, and to protect non-combatants, whether they are the wounded, sick or captured soldiers or sailors, and especially civilians.   

Although war crimes are usually committed by military personnel, they may also be perpetrated by civilians. In this way, all categories of persons may be held criminally liable for violations of the rules of war. A war crime must have a sufficient link to an armed conflict and in this way be closely related to the hostilities taking place. This distinguishes it from ordinary criminality.  

The 1949 Geneva Conventions and Additional Protocols form the core of international humanitarian law. They embody fundamental principles, such as military necessity, humanity, distinction and proportionality.  The principle of humanity forbids the infliction of suffering, injury or destruction not actually necessary for legitimate military purposes and is applicable to military purposes and choice of weapons.

Russia’s invasion of Ukraine is an illegal war of aggression

In 1923, just five years after the end of the First World War, the US Secretary of State Charles Evans Hughes, who would subsequently serve as Chief Justice, stated that “war should be made a crime, and those who instigate it should be punished as criminals.”

International humanitarian law developed when there was no international prohibition on the right to wage war. Since the adoption of the UN Charter in 1945, there is a general prohibition on the use of force by states except in accordance with the provisions of the Charter.  The legality of the resort to armed conflict by states is, therefore, a question of international law, while the conduct of those engaged in hostilities is governed by international humanitarian law.  Individuals violating international law governing the use of force may be charged with the crime of aggression or crimes against peace, while those violating humanitarian law may be prosecuted for war crimes.  In this way, international humanitarian law applies to all parties, i.e. to those lawfully resorting to the use of force as well as to those deemed to be acting unlawfully.   

The invasion of Ukraine by Russia is a violation of the UN Charter, which under Article 2(4), prohibits the “threat or use of force against the territorial integrity or political independence of any state.” There were no grounds to support the claim by Russia of self-defence. Indeed, all of Putin’s claims have been thoroughly refuted as pretexts for the invasion, which constitutes an act of aggression and is contrary to international law. Putin, as president, may also be individually responsible for the crime of aggression, one of the core crimes set out in the Rome Statute of the International Criminal Court. However, there are significant legal hurdles to be overcome before this would be possible as Russia is not a party to the International Criminal Court statute.   

Accountability for war crimes

The most significant challenge for international humanitarian law is enforcement. Gen. Aleksandr Dvornikov, Russia’s new commander in Ukraine, oversaw the Kremlin’s brutal campaign in Syria. It is unfortunate that there has been little or no accountability for crimes committed in Syria and Yemen. This has given Putin and his cohorts the wrong message regarding accountability.

The UN Commission for the Investigation of War Crimes was established in the aftermath of World War II in order to prepare the groundwork for the prosecution of war criminals.  This led to the establishment of the International Military Tribunals at Nuremberg (1945-46) and Tokyo (1946-48). In more recent times, international criminal tribunals and a range of special courts were established. The creation of the International Criminal Court marked a significant advance in accountability. Concern about implementing humanitarian law was one of the driving forces behind the proposals to create the Court.   

A fundamental principle of international humanitarian law is that of individual criminal responsibility. It is critical that all violations are investigated and those responsible held accountable. However, all crimes must be proved beyond a reasonable doubt.  International courts and tribunals are chiefly concerned with the senior political and military leaders responsible for what are called ‘atrocity crimes.’  In this context, it is important to note that there is also evidence of crimes against humanity being committed in Ukraine.  These occur when a civilian population is deliberately attacked in a widespread or systematic manner.  There have also been allegations of genocide by all sides.  The threshold for proof in the case of genocide is very high and requires intent to destroy a group based on nationality, race, religion or ethnicity be established. These latter crimes should not be confused with war crimes, and they do not require a link to an armed conflict, but in practice most often occur in situations of conflict.  It is noteworthy that an attack on a civilian target may be evidence of one or all of these crimes, depending on the context.

The war in Ukraine is an international armed conflict involving large-scale conventional military forces, with catastrophic humanitarian consequences of a scale not seen in Europe since the break-up of the former Yugoslavia in the 1990’s. In this way the situation may appear unprecedented. However, from the perspective of international humanitarian law this conflict does not give rise to a need to create a new rule book: humanitarian law was designed to limit the consequences of exactly such conflicts. The key challenge remains how to ensure their enforcement and how to hold accountable those who are responsible for violations.  At the end of the Yugoslav conflict, the UN Security Council established the International Criminal Tribunal for the Former Yugoslavia.  There is no prospect of this precedent being followed when the war in Ukraine ends. However, since the referral of the situation in Ukraine to the International Criminal Court, it now has jurisdiction.  

A major problem for accountability remains the selective policies of the major powers.  The Trump Administration imposed sanctions against the Court’s prosecutor and other staff.  The former US Secretary of State Mike Pompeo denounced the International Criminal Court as a “kangaroo court”. He threatened that the US would punish the Court employees for any investigation or prosecution of Americans in Afghanistan or for prosecuting Israelis for alleged abuses against Palestinians. Ireland, to its credit, has been a consistent supporter of the Court. It has also provided aid to train investigators. One of the earliest international criminal investigators courses was run by the Institute for International Criminal Investigations at the Irish Centre for Human Rights, University of Galway in 2002. Investigating war crimes poses much greater challenges than investigating serious domestic crimes, and usually takes many years and significant resources. At the time of writing Ukraine is a crime scene and there are unprecedented resources going into investigating what is happening there.  Furthermore, there are now many international and national precedents for the successful prosecution of alleged war criminals.