The “crime of aggression” is one of the four core crimes within the jurisdiction of the International Criminal Court (ICC), alongside genocide, crimes against humanity, and war crimes. However, unlike the other three crimes, over which the ICC Prosecutor has broad and independent authority to investigate and prosecute, the exercise of jurisdiction over the crime of aggression has remained constrained since its inclusion in the Rome Statute over 27 years ago.

This article examines the urgent need to amend the Statute to ensure parity among all four core crimes and to strengthen the coherence and effectiveness of the Court’s mandate.

The concept of a crime of aggression is not novel in international law as its origin can be traced back to the Nuremberg and Tokyo trials held by the Allied Powers following World War II, and like its World War II precursor, the crime of aggression strikes at the heart of international peace and security by attacking the very basis of state sovereignty.

Unfortunately, despite being recognised as the worst form of the illegal use of force, aggression has been treated differently from the other core crimes. At the Rome Conference in 1998, the inclusion of aggression in the ICC’s mandate was agreed upon, but its definition and the conditions under which the Court could exercise jurisdiction were to be addressed at a future date.

It wasn’t until the Kampala Review Conference in 2010, more than a decade later, that states finally adopted a definition of the crime of aggression and set out the conditions for the ICC’s jurisdiction. Even with this progress, the crime did not become fully actionable until 2017, when States Parties activated the ICC’s jurisdiction over the crime, which took effect on 17 July 2018.

But despite the seeming giant stride, the procedural features of the crime of aggression remains much more complex and restrictive compared to the other core crimes. For example, Article 15bis of the Statute creates a consent-based jurisdictional regime, which primarily preserves the Court’s judicial independence, but limits its scope of jurisdiction. Apart from situations arising from Security Council referral which the Court can investigate and prosecute without any further aggression-specific conditions, only in certain cases can the Court exercise jurisdiction.

In particular, Article 15 b is uniquely and unfairly prevents the ICC from exercising jurisdiction over any crime of aggression involving a non-State Party, including when nationals of non-State Parties are the alleged perpetrators, and it gratuitously allows States Parties to opt out of the Court’s jurisdiction over the crime of aggression.

Respectfully, these crippling jurisdictional constraints are most untenable. While the other core crimes can be prosecuted with broader and less restrictive criteria, the crime of aggression is inhibited by hurdles that are not required for the prosecution of other core crimes. This, in my view, creates a hierarchy of international crimes having the potential to weaken the enforcement of international law, especially when it comes to preventing acts of aggression that often bring about other serious violations.

The ongoing conflict in Ukraine offers a rare illustration of the egregious shortcomings in the current legal framework. Though, the ICC can exercise jurisdiction over war crimes and crimes against humanity committed within Ukraine, yet, due to the fetters around the crime of aggression, the ICC is unable to investigate or prosecute those responsible for the unlawful invasion that triggered the war. This gap exists because neither Ukraine (until recently) nor Russia is a state party to the Rome Statute, and Russia has not ratified the amendments that allow the court to prosecute aggression.

Even if it had, the ICC would still face obstacles, as current rules prevent the court from exercising jurisdiction over aggression without a United Nations Security Council referral – a highly unlikely event given the political dynamics in the Council where Russia holds veto power.

The acknowledgement that the ICC, has failed to hold Russia to account has inevitably pushed the international community to work towards the establishment of an ad-hoc tribunal to investigate and prosecute crimes of aggression committed against Ukraine! This situation has laid bare a fundamental flaw in the international justice architecture, that without full jurisdiction over the crime of aggression, accountability remains unattainable. The ICC’s inability to prosecute those responsible for starting the war, while it investigates crimes committed during the conflict, creates a piecemeal form of justice.

It allows the brains behind the acts of aggression to evade accountability, leaving victims without the full scope of legal redress they deserve. Moreover, it sends a message that while the conduct of war may be put under scrutiny, the individuals responsible for the planning, preparation and initiation of the war itself can go unpunished. This apparent duplicity undermines the credibility of the ICC and diminishes the overall deterrent effect of international law.

Comprehensive accountability requires harmonising the ICC’s jurisdiction over all core crimes, including aggression. The Assembly of States Parties (ASP) must act to close these legal loopholes that allow powerful states to escape sanctions for aggressive actions.

The harmonisation of aggression with other core crimes would ensure that justice is not only rendered for the atrocities committed during war but also for the illegal acts that precipitate war itself. African countries, many of which have experienced the devastating effects of illegal uses of force, have a significant stake in the push for an ICC regime that puts the crime of aggression on the same platform as other core crimes.

The special treatment given to the crime of aggression under the current framework leaves smaller and more vulnerable states exposed to the threat of unmitigated aggression, often without any legal recourse. A harmonised regime would better protect African nations from external violations of sovereignty, while also strengthening the broader international legal order.

Moreover, uniting in support of a more combative crime of aggression regime aligns with Africa’s long-standing advocacy for greater equity in global institutions. African countries have often expressed concerns about the imbalance in how international law is applied, with the perception that the ICC has disproportionately targeted African leaders while failing to hold powerful states accountable for their actions.

By pushing for harmonised rules on aggression, African nations can address this perceived bias, ensuring that the ICC operates more fairly and without favoring certain regions or countries. This would help rebuild trust in international institutions and strengthen Africa’s role in promoting global justice.

Proposal for amendments
Abolish the Opt-Out Clause for States. Currently Article 15 bis(4) allows states parties to opt out of the court’s jurisdiction over the crime of aggression by filing a declaration. it is proposed that the opt-out provision in Article 15 bis(4) be removed, thereby ensuring that all states parties to the Rome Statute are automatically subject to ICC jurisdiction for the crime of aggression, in the same manner as other core crimes. (ii). Expand the definition of Aggression to cover a wider range of Acts As things stand today, Article 8 bis of the Rome Statute defines the crime of aggression, limiting it to the use of armed force by a state that violates the UN Charter. This primarily covers military actions such as invasions, bombings, or blockades.

It is suggested, that Article 8 bis should be broadened to include non military acts of aggression, such as economic coercion, cyber attacks, or other forms of interference that violate a state’s sovereignty, integrity, or independence, but fall short of direct military action. (iii). Equalise procedural rules for aggression and other core crimes existing Article 15 bis(3) and Article 15 ter(3) set additional procedural requirements for investigating aggression, such as requiring confirmation that aggression occurred and involving a higher threshold than for other core crimes.

To achieve parity, Articles 15 bis and 15 ter should be amended to streamline procedural requirements for prosecuting the crime of aggression, bringing it in line with the more straight forward procedures for other core crimes, as set out in Articles 13–15 of the Rome Statute. (iv). Clarify and Strengthen Leadership Accountability for Aggression In its current form, Article 25(3 bis) limits individual responsibility for the crime of aggression to those in positions of effective control or leadership, but this can be ambiguous in practice.

It is proposed that ICC States Parties should elucidate and strengthen Article 25(3 bis) to ensure that political and military leaders who are directly involved in decision-making are held responsible for acts of aggression. This could involve adding more explicit language regarding what constitutes “effective control” to avoid loopholes and ensure accountability for heads of state and senior leaders.

By making these amendments, the Rome Statute could restore parity between the crime of aggression and other core crimes to ensure that the initiation of unlawful wars is prosecuted with the same vigor as atrocities committed during conflicts. I would like to conclude by stating that justice for the crime of aggression by all States Parties isn’t a choice, it’s a responsibility all member states of the United Nations undertook when they all signed up on the United Nations Charter.

For this reason, we can’t afford to keep dancing around the crime of aggression like it is volcanic lava!

Jegede, Executive Director, Legal Watch and Human Rights Initiative, is a former United Nations Prosecutor.