Analysis written by Robbert van de Bovenkamp
Introduction
On 15 December 2025, the Appeals Chamber of the ICC rejected, by a narrow majority decision, an appeal made by the State of Israel. Israel responded to this ruling by stating that the ICC Appeals Chamber’s decision “denied Israel’s right to receive advance notice, as demanded by the principle of complementarity particularly with regard to a democratic state with an independent and robust judicial system.”[1]
At issue before the Appeals Chamber, was Israel’s request for a new notice under article 18(1) of the Rome Statute. In Israel’s view, a couple of State referrals that were made in 2023 and 2024 to the ICC would “identify a new situation of crisis” and justify another article 18(1) notice by the Office of the Prosecutor (hereafter: Prosecutor).[2] Importantly, as argued by Judge Luz del Carmen Ibáñez Carranza in her dissenting opinion, the grounds of appeal raised by Israel entail essential issues dealing with the principle of complementarity; a core feature of the Rome Statute system. Article 18(1) provides that States concerned must receive early notice of the Prosecutor’s determination that a reasonable basis exists to commence an investigation. Such notice is important, as to allow a State under article 18(2) to request the Prosecutor to defer investigations where the same matter is being investigated by their national judicial systems, thereby giving effect to the principle of complementarity.
This piece of writing will provide an overview of the procedure before the ICC, dive into the principle of complementarity and look at the Israeli claims concerning article 18 of the Rome Statute.
Overview
On 22 May 2018, the Palestinian Authority referred to the Prosecutor the situation related to “past, ongoing and future crime within the court’s jurisdiction, committed in all parts of the territory of the State of Palestine”. Five years later, on 17 November 2023, five States Parties to the ICC Statute submitted a referral, “requesting the Prosecutor to vigorously investigate crimes under the jurisdiction of the Court allegedly committed within the context of the Situation in Palestine.”[3] This was followed by another referral of two State Parties on 18 January 2024, in which they also requested the Prosecutor to investigate “crimes that would have taken place concerning the situation in the State of Palestine.”[4]
On 23 September 2024, Israel submitted before Pre-Trial Chamber a request for an order to “the Prosecutor to give an article 18(1) notice setting out the new defining parameters of his investigation in this Situation, or in any other Situation that has now been constituted as a result of the two referrals made by a total of seven States Parties following 7 October 2023”. On 21 November 2024, the Pre-Trial Chamber issued a decision in which it rejected the Article 18 Request. On 27 November 2024, Israel filed its notice of appeal against the Pre-Trial Chamber’s decision.
On 15 December 2025, the Appeals Chamber rejected Israel’s assertion that the Pre-Trial Chamber “erred in failing to find, and giving no reasons to reject, Israel’s submission that a new Situation was triggered by referrals following 7 October 2023.” In this appeal case, Israel contended that the Court’s jurisprudence has rejected the practice of defining a situation without limitations as to context or duration “as incompatible with […] ‘the proper functioning of the principle of complementarity’.”[5]
Principle of Complementarity
The principle of complementarity establishes that the Court complements, and does not substitute, national jurisdictions, which have the primary responsibility to investigate and prosecute the most serious crimes of concern to the international community. As noted by Judge Luz del Carmen Ibáñez Carranza the principle of complementarity is a core feature of the Rome Statute system, with the judicial duty to comply with the guarantees of due process of law, and to the need to ensure predictability of the law and judicial certainty.[6] It is a core principle that governs the exercise of the Court’s jurisdiction and it is expressly stated in the Preamble of the Statute.
The background behind the complementarity regime show that it is the product of a delicate balancing exercise. In the course of the negotiations for the Statute, some States highlighted the need for ensuring respect for national sovereignty and the primacy of domestic proceedings, and only accepted the complementarity provisions in the Statute when satisfied that these concerns were carefully addressed. The Statute ensures respect for national sovereignty by clearly and objectively defining the criteria on which the Court’s interventions can be based.
In her dissenting opinion, Judge Luz del Carmen Ibáñez Carranza noted “it is the Court’s duty to uphold the principle of complementarity as envisaged by the Rome Statute system. It is not for the Prosecutor alone, and on his or her own accord, to make determinations that could undermine or otherwise affect this principle and regime.”[7]
The case for a deferral request
As the Appeals Chamber of the ICC once stated: “no State should have to face the prospect of being found wanting in this regard without at least being given an opportunity to explain itself. This is why articles 18 and 19 of the Statute provide several procedural avenues for States to correct the Prosecutor’s assessment of their domestic efforts.”[8]
On 1 May 2024, Israel sent a letter to the Prosecutor, requesting him to “defer any investigation [his office] may be conducting in relation to any alleged criminal acts attributed to Israeli nationals or others within Israel’s jurisdiction, in favour of Israel’s processes for review, examination, investigation and proceedings under its national legal system.”[9] The request came, after seven States had invoked the court’s jurisdiction for the first time in respect of new crimes, new circumstances, and new potential perpetrators – a new “situation of crisis”.[10] The answer to the request, however, was negative. The Prosecutor responded to the deferral request, indicating that, having “expressly declined to make an application for deferral of the investigation within the prescribed time limit”, Israel has “no standing now, under the Statute, to make such an application”.[11]
In return, before the Pre-Trial Chamber, Israel asserted that it “has primary jurisdiction and is best placed to investigate allegations of the sort raised by the Prosecutor, given the access required to relevant evidence, information and persons.”[12] In line with the principle of complementarity, a proper notification under article 18(1) would allow it to exercise its right to assert its primary jurisdiction, and would facilitate its ability to respond to the Prosecutor in accordance with article 18(2). The Pre-Trial Chamber, however, rejected Israel’s article 18 request. Israel then appealed this decision, bringing it to the Appeal Chamber where a majority did not “discern an error in the Pre-Trial Chamber’s finding .“[13]
Dissenting to this Appeal’s Chamber’s ruling, Judge Luz del Carmen Ibáñez Carranza notes that “the Prosecutor did not follow the procedure set out in the Statute and the Regulations and provided no legal basis for this departure (…)”.[14] Moreover, reacting to the Pre-Trial Chamber’s decision, she states that it “erred in law and procedure, by failing to address Israel’s submissions and give reasons for its rejection of Israel’s argument.”[15] In this regard she notes that, “given the serious concerns (…) about the Prosecutor’s compliance with the referral procedure in this instance, I consider that the Pre-Trial Chamber ought to have addressed this issue and set out its findings clearly, bearing in mind the importance of the complementarity regime and the rights of States.”[16] The dissenting Judge then concludes by noting that, “had the Pre-Trial Chamber duly considered Israel’s arguments, it would have had to address the impact of the Referrals on the determination of whether a new situation was established and whether the Prosecutor’s duty to give a new notification pursuant to article 18(1) of the Statute was triggered.”[17]
Conclusion
Israel has emphasized and placed on record that its robust legal system has jurisdiction over all of the issues raised, as well as any other alleged wrongdoing by Israeli nationals in the context of the current conflict, and professional and independent mechanisms to investigate specific incidents and policy-level issues.[18] This reflects the heart of the principle of complementarity, in which not the ICC but national jurisdictions have the primary responsibility to investigate and prosecute the most serious crimes of concern to the international community. This was also the basis on which Israel requested the Prosecutor to give an article 18(1) notice setting out the new defining parameters of his investigation following 7 October 2023. In line with the principle of complementarity, a proper notification under article 18(1) would have allowed Israel to exercise its right to assert its primary jurisdiction. Both the Prosecutor, and the Pre-Trial Chamber should have considered Israel’s arguments, bearing in mind the importance of the complementarity regime and the rights of States. By not doing so, it denied Israel the right to properly exercise its national jurisdiction.
[1] Israel rejects the ICC Appeals Chamber’s decision Ministry of Foreign Affairs
[2] On 9 March 2021, the Prosecutor had provided notice, pursuant to article 18(1) of the Statute, of the initiation of the investigation to Israel. However, Israel contends that 7 October 2023 and the consequent referral of several State Parties had created ‘a new situation of crisis’ and justified another notice.
[3] The referral was submitted by the Republic of South Africa, the People’s Republic of Bangladesh, the Plurinational State of Bolivia, the Union of the Comoros, and the Republic of Djibouti.
[4] The referral was submitted by the Republic of Chile, and the United Mexican States.
[5] Judgement on the appeal of the State of Israel against Pre-Trial Chamber I’s “Decision on Israel’s request for an order to the Prosecution to give an Article 18(1) notice”, para 61.
[6] Dissenting Opinion by Judge Luz del Carmen Ibáñez Carranza, para 11
[7] Dissenting Opinion by Judge Luz del Carmen Ibáñez Carranza, para 30
[8] Yekatom Admissibility AD, para. 42.
[9] Judgement on the appeal of the State of Israel against Pre-Trial Chamber I’s “Decision on Israel’s request for an order to the Prosecution to give an Article 18(1) notice”, para 9.
[10] Abridged Request for an Order Requiring an Article 18(1) Notice, and Staying Proceedings Pending Such a Notice, para 2.
[11] Judgement on the appeal of the State of Israel against Pre-Trial Chamber I’s “Decision on Israel’s request for an order to the Prosecution to give an Article 18(1) notice”, para 10.
[12] Ibid, para 9.
[13] Judgement on the appeal of the State of Israel against Pre-Trial Chamber I’s “Decision on Israel’s request for an order to the Prosecution to give an Article 18(1) notice”, para 85.
[14] Dissenting Opinion by Judge Luz del Carmen Ibáñez Carranza, para 41
[15] Ibid, para 54
[16] Ibid, para 41
[17] Ibid, para 54
[18] Toward a Fuller Understanding of Objections to ICC Prosecutor’s Request for Netanyahu and Gallant Arrest Warrants
