On 9 July 2025, States Parties to the International Criminal Court committed by consensus to strengthen the Court's jurisdiction over the crime of aggression by 2029. A German international law professor from the University of Cologne told the 2026 Nuremberg Forum on 7 October that this pledge can finally fulfil Robert Jackson's 1945 promise — if governments resolve a "trap for the innocent" risk.

Addressing the 80th anniversary of the Nuremberg Judgment in Court Room 600, the speaker traced the 80-year arc from the tribunal that convicted Nazi leaders to the ICC's current jurisdictional bottleneck.

What did Nuremberg actually decide?

The International Military Tribunal at Nuremberg found that "to initiate a war of aggression" is "the supreme international crime." Yet the tribunal applied that principle only to the defeated Axis powers. U.S. Chief Prosecutor Robert Jackson warned in his opening statement that the law could not coherently limit itself this way:

"While this law is first applied against German aggressors, the law includes, and if it is to serve a useful purpose it must condemn aggression by any other nations, including those which sit here now in judgment."

Jackson's promise "remained unfulfilled" for more than seven decades, the speaker said. The Nuremberg precedent won endorsement from the UN General Assembly, confirmation at Tokyo, and restatement by the International Law Commission. Yet it stayed marginalised until Russia's full-scale invasion of Ukraine on 24 February 2022.

Why did the ICC stay silent on Russia?

One day later, on 25 February 2022, the ICC Prosecutor issued a terse statement: "Given that neither Ukraine nor the Russian Federation are State Parties to the Rome Statute, the Court cannot exercise jurisdiction over this alleged crime in this situation."

Three days after that, on 28 February 2022, lawyer Philippe Sands asked in the Financial Times: "Why not create a dedicated international tribunal to investigate Putin and his acolytes for the crime of aggression?"

That question "marks the beginning of the end of the marginalization of the crime of aggression," the speaker said. Ukraine, joined by Nobel Peace Prize laureate Oleksandra Matwijtschuk of the Centre for Civil Liberties, pressed the case. Poland, the Baltic States, and Finland — all targets of Stalin's aggression in the 1940s — lent vocal backing. Britain and France, traditionally cool to the crime's prosecution, eventually joined.

Where do the 2025 negotiations stand?

Negotiators have now put the basic legal framework for a Special Tribunal for the Crime of Aggression against Ukraine in place under the Council of Europe's Enlarged Partial Agreement. Ukraine's chief negotiator, Ambassador Anton Korynevych, sat in Court Room 600 and recently received the Robert H. Jackson Center's Joshua Heintz Award for Humanitarian Achievement.

States Parties to the ICC now work to align the Court's aggression-jurisdiction regime with those covering genocide, crimes against humanity, and war crimes. Costa Rica, Germany, Sierra Leone, Slovenia, and Vanuatu tabled a text proposal last year. The Assembly of States Parties convened a special session with this single agenda item. On 9 July 2025 they committed, by consensus, to "strengthening the Court's jurisdiction over the crime of aggression."

The diplomatic process aims at completion in 2029. "Three years from now seems a long time," the speaker warned, "but experienced diplomats know well that the time for decision is actually almost around the corner."

What is the 'trap for the innocent' risk?

The remaining sticking point echoes a century-old warning from British Foreign Secretary Austen Chamberlain, who in 1927 feared a definition of aggression could become "a trap to the innocent." Australia, Britain, Canada, France, and New Zealand have all pressed, between the lines of diplomatic interventions, for guarantees that a future ICC prosecutor and a majority of judges will not investigate their leaders for involvement in contested uses of force — including genuine humanitarian intervention.

The threshold clause of Article 8 bis requires an act that "by its character, gravity and scale, constitutes a manifest violation of the Charter of the United Nations." That wording is "abstract" and "in obvious need of interpretation," the speaker conceded. Yet scholars widely agree the threshold must be narrowly construed. China and Russia, both at Kampala, accepted the final text. Chinese delegate Zhou Lulu wrote that "the threshold clause reflects customary international law." Russian delegates Gennady Kuzmin and Igor Panin stated: "Russia is satisfied with the outcome of the Review Conference with regard to the definition of the crime of aggression."

The speaker proposed three additional safeguards:

• A future prosecutor could give advance interpretive guidance on the threshold clause
• States Parties could add a Rule of Procedure and Evidence requiring a qualified majority in the Pre-Trial Division to authorise an investigation
• Negotiators could adopt an additional interpretive understanding on the threshold's stringency

Why does the timing matter?

The current US administration has abandoned its Nuremberg legacy, the speaker said, and now threatens those working to fulfil Jackson's promise. This posture is "contagious." It marks a descent from "unlawfulness to lawlessness."

Benjamin B. Ferencz, the chief architect of the post-war aggression charge, captured the underlying obstacle decades ago: "The vital ingredient that was really lacking was the political will of a few major powers that persisted in their refusal to accept rational international controls over the use of military force."

South African delegate André Stemmet flagged the same legitimacy gap during the Kampala talks: "The major weakness is, of course, that Non-State Parties [...] will be able to commit aggression with a sense of impunity."

If States Parties resolve the threshold question, the speaker concluded, "Nuremberg's shining promise of a principled and meaningful prosecution and adjudication of the crime of aggression can be fulfilled in 2029. And this by consensus instead of a vote."