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The law of war
Explosion in apartment building that came under fire from Russian army in Mariupol, Ukraine PIC: Shutterstock

01 Apr 2022 / Rule of law Print

Jus in bello

International humanitarian law regulates the methods and means of warfare. Its aim is to limit human suffering, even in extreme situations such as armed conflict. Ray Murphy assesses the conflict in Ukraine using IHL principles.

The conflict in Ukraine has highlighted the importance of the rule of law in international relations, and the ongoing hostilities there have focused attention on the laws of war – or ‘international humanitarian law’ as it is now more commonly known.

International humanitarian law regulates the methods and means of warfare. Its aim is to limit human suffering, even in extreme situations such as armed conflict. It provides the legal framework and definition of what constitutes a war crime.

The most recent attempt to codify war crimes can be found in article 8 of the Rome Statute of the International Criminal Court. It refers to a range of actions such as intentionally directing attacks against civilians or civilian objects; attacking or bombarding, by whatever means, towns, villages, dwellings or buildings that are undefended; or intentionally causing starvation.

Origins and key principles

At present, it is not possible to commit a war crime in Ireland. This is not because of any statutory gap in the laws governing such crimes; rather, it reflects the fact that there is no armed conflict taking place in Ireland.

Therefore, the first fact that must be established when investigating war crimes is whether or not there is an armed conflict taking place, and then link the alleged crime to that conflict.

In this way, an ‘armed conflict’ triggers the application of international humani-tarian law and is said to exist, among other things, once fighting breaks out between the armed forces of two states, or when the armed forces of one state invade the territory of another. It is beyond doubt that the situation in Ukraine constitutes an international armed conflict and triggers the application of international humanitarian law.

The Geneva Conventions and their additional protocols form the core of international humanitarian law. These embody a number of fundamental principles, chiefly that of 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. It is applicable to military purposes and choice of weapons.

The essence of the ‘principle of distinction’ is that a distinction must always be drawn between combatants and non-combatants. Two key concepts are that of ‘protected objects’ and ‘military objectives’. These are defined in articles 52 to 56 of Additional Protocol I to the Geneva Conventions and reflect customary international law.

‘Protected objects’ are those generally used for civilian purposes that do not effectively contribute to the war effort and whose destruction does not offer a definite military advantage. This should be contrasted with ‘military objectives’, which, by their nature, location, purpose or use, make an effective contribution to military action. Their total or partial destruction, capture, or neutralisation must offer a definite military advantage.

Some of the weapons being used by the Russians in Ukraine raise serious concerns. The Bellingcat investigative website has been collecting evidence of the suspected use of cluster rockets and their submunitions.

They are inherently indiscriminate and pose an immediate and long-term serious threat to civilians. The use of multiple-launch rocket systems and cruise missiles against civilian areas during the invasion has also been condemned by Amnesty International.

Illegal war of aggression

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 under article 51 of the charter. Indeed, all of Putin’s claims have been challenged 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.

Putin’s thinly veiled references to a resort to nuclear weapons should other states intervene militarily are also unlawful threats of force, contrary to the UN Charter. Today, it is widely recognised that the use of nuclear weapons is contrary to international humanitarian law or the law of armed conflict, primarily because of their indiscriminate and disproportionate nature, as well as their inability to distinguish between military targets and civilian persons or infrastructure.

In 1994, the International Court of Justice found such use – or threatened use – to be illegal. States do not have unlimited freedom of choice in the weapons they use.

The main circumstance in which the court could not reach a conclusion, when the survival of a state is at stake, is not at issue for Russia in the present crisis.

Individual responsibility

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.

International courts and tribunals are chiefly concerned with the senior political and military leaders responsible for so-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 the 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 the establishment of an intention to destroy a group based on nationality, race, religion, or ethnicity.

These latter crimes should not be confused with war crimes, and they do not require a link to an armed conflict; however, in practice, most often occur in situations of conflict. Needless to say, an attack on a civilian target may be evidence of one or all of these crimes, depending on the context.

‘Grave breaches’ cover the most serious violations of the Geneva Conventions that may be committed in the course of an international armed conflict. Examples include wilful killing and extensive destruction of property not justified by military necessity.

All states, including Ireland, have criminal jurisdiction to try those accused of ‘grave breaches’ – whatever their nationality or wherever the crimes were committed. This is referred to as ‘universal criminal jurisdiction’.

In addition, the international community has, on occasion, acted to create machinery to repress breaches of humanitarian law. Two leading examples were the Nuremberg War Crimes Trials (under which the Nazi leadership was tried), and the International Criminal Tribunal for the Former Yugoslavia.

More recently, the establishment of the International Criminal Court heralded a major development in international mechanisms to ensure accountability. It is important to note that, while the Rome Statute of the International Criminal Court provides the most recent definition of war crimes, such crimes have existed for centuries, and the court is merely an additional mechanism for enforcement of the law.

Investigating war crimes is not like investigating serious domestic crimes – it takes many years and significant resources. Since the referral of the situation in Ukraine to the International Criminal Court, it now has jurisdiction. Although many international courts will apply a combination of common-law and civil-law procedures, the rules of evidence and burden of proof are well established.  

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Ray Murphy
Dr Ray Murphy is a professor at the Irish Centre for Human Rights, School of Law, National University of Ireland Galway. He is also on the faculty of the International Institute for Criminal Investigations (The Hague) and is a former captain in the Irish Defence Forces.