The Appeals Chamber of the International Criminal Court (ICC) affirmed on December 15 the admissibility of the case against Israeli leaders, Benjamin Netanyahu and Yoav Gallant, relating to the events that followed the October 7, 2023 attack by Hamas against Israel. Israel had argued that the Office of the Prosecutor (OTP) had failed to formally notify Israel of the opening of an ICC investigation into Israel’s response to the October 7, 2023 attack. It further claimed that the failure to notify deprived it, practically speaking, of the ability to exercise its legal right to investigate the alleged crimes in lieu of the ICC, a breach of the Court’s core principle of complementarity.
But the Appeals Chamber rejected this view by a narrow majority (3-2). Instead, it accepted the OTP’s position that a 2021 notification regarding the investigation of certain alleged crimes occurring since 2014 in the context of the Israeli-Palestinian conflict fulfilled the formal duty to notify. Two judges disagreed and opined that the Pre-Trial Chamber that first reviewed Israel’s claim should have examined the impact that numerous new referrals submitted by ICC member-States after October 7 had on the duty to notify. Furthermore, one of the majority judges wrote that the Prosecutor should continuously monitor the need to provide an updated notification when circumstances change. Still, he was not convinced that in the present circumstances the Prosecutor failed to properly exercise such discretion.
The upshot of the decision is that, as a practical matter, the arrest warrants issued by the ICC in 2024 against Israeli Prime Minister Netanyahu and former Defense Minister Gallant remain in force. In effect, the judgment marks a choice by the Court not to take an exit ramp, which could have put on hold the controversial warrants against Netanyahu and Gallant. Still, two other preliminary motions challenging the validity of the arrest warrants remain pending: One is based on the unclear legal status of the State of Palestine and its lack of jurisdiction over Israeli nationals; a second motion involves Israel’s request to disqualify ICC Prosecutor Karim Khan from the case due to a lack of perceived impartiality and quash the warrants he requested the Court to issue. A third motion to suspend the arrest warrants while the question of jurisdiction is being considered was rejected by the Pre-Trial Chamber on Oct. 17.
Beyond its importance to the Netanyahu and Gallant cases, the judgment is also notable for the Court’s narrow interpretation of the complementarity principle – a principle that envisions the ICC as an institution that is supposed to complement national criminal systems, not replace them. Article 18 of the Rome Statute, the Court’s founding treaty, lays out the formal notification procedure required when an investigation begins, in order to facilitate giving the right of way to domestic investigations. Arguably, the recent judgment detaches this procedure from its stated purpose of affording States a reasonable chance to claim jurisdictional primacy and undertake their own criminal investigations of conduct that falls under the scope of the ICC Statute. This outcome arguably goes against the Court’s declarative embrace of positive complementarity, and adds another layer of apprehension to an already troubling sequence of events surrounding Khan and the investigation (see e.g., here). When added to the Court’s rejection of non-members’ head of state immunity, the picture that emerges from the recent judgment is one of limited protection afforded by the ICC to sovereign rights and legal interests of non-ICC States.
The Court’s Judgment
In its judgment, the Appeals Chamber walked through the relevant chain of events: the 2018 Palestinian referral of a situation to the ICC, Prosecutor Fatou Bensouda’s 2021 decision to open an investigation and notify Israel, Israel’s evasive response to the initial notification, the post-October 7 referrals to the Court by several States, Israel’s May 1, 2024 request for deferral (which was rejected by the OTP for being allegedly submitted after the deadline), and the Pre-Trial Chamber’s rejection of Israel’s Article 18(1) challenge (issued in November 2024). It then moved to review Israel’s three objections to the 2024 decision.
First, the Court addressed Israel’s claim that the 2018 referral and 2021 notification did not cover post-October 7 events since the referral and notification were not intended to cover all crimes committed during an ongoing armed conflict. In particular, the 2021 notification referred only to Israel’s settlement policy and to two specific episodes (the 2014 Gaza hostilities and the violent clashes along Gaza’s border with Israel that took place in 2018). The Court held that the reference in the 2021 notification to war crimes implied a legal position that an armed conflict exists, and that the notification identified the parties to the armed conflict (Israel and Palestinian armed groups, including Hamas). Hence, it held that an armed conflict was one of the defining parameters of the 2021 notification. With regard to the claim underscoring the temporally defined nature of that notification, the Court noted that the Palestinian 2018 referral, against which the notification should be read, was not time limited. It cited an earlier decision in support of the proposition that “there is no expectation at this stage of the proceedings that the Prosecutor should notify States of every act he or she intends to investigate.” It also held that the 2021 notification alluded to crimes allegedly committed in 2014 as merely illustrative of patterns and forms of criminality, and stated that it should not prejudice the future scope of investigation of crimes falling under the same situation.
This formulation reflects, according to the Court, “the relationship between the provisions in the Court’s legal texts regulating the threshold for commencing an investigation under Article 53(1) of the Statute, the requirement to provide sufficiently specific information to a State for the purposes of Article 18(2) of the Statute, and the Prosecutor’s prerogative to continue the investigation within the parameters of the Palestine Situation.” As a result, the Court accepted the OTP’s position that the post-October 7 investigation covers “conduct committed in the context of the same type of armed conflicts, concerning the same territories, with the same alleged parties to these conflicts,” to which the 2018 referral and 2021 notification alluded.
Second, regarding Israel’s claim that the post-October 7 referrals triggered a new situation that would reset the clock, the majority of the Court held that Israel did not directly raise the matter before the Pre-Trial Chamber. Furthermore, the majority took the position that the post-October 7 referrals were connected to the 2018 referral and were designed to encourage the Prosecutor to advance the pre-existing investigation. It surmised that “[s]uch references are, thus, compatible with the notion that, in the early stages of the investigation, the Prosecutor is not in a position to identity or anticipate all potential cases for investigation and that, as the investigation progresses, it may come to encompass alleged crimes not previously identified or anticipated.”
Third, with respect to Israel’s claims that the factual context changed dramatically after October 7 and that the 2021 notification was not specific enough to cover it, the Court noted that the Pre-Trial Chamber found in 2024 that the 2021 notification was sufficiently specific and that the request for arrest warrants fell within its defining parameters. It also noted that defining parameters are case-specific and have to be considered against the scope of the original referral (which in the present case was broad in nature and encompassed both war crimes and crimes against humanity). It further concluded that “the alleged crimes display a continuity in pattern, even though a certain shift in circumstances may have occurred as a result of the events on and after 7 October 2023.” Put differently, the alleged crimes are sufficiently linked to the situation of crisis referred to the Court in 2018.
The Dissenting Opinions and the Concurring Opinion
Judge Luz Del Carmen Ibáñez Carranza dissented from the majority. She accepted Israel’s claim that the Prosecutor failed to inform the President of the ICC of the post-October 7 referrals in apparent violation of Regulation 45 of the Court’s regulations and that this failure – which might have prevented the Court from determining that a new situation and a new duty of notification to Israel exists – was not properly considered by the Pre-Trial Chamber. Specifically, the Pre-Trial Chamber should have considered whether the new referrals gave rise to a new situation, and the majority should not have reviewed the question de novo. She also criticized the Pre-Trial Chamber for failing to consider whether, as a non-State party, Israel was even required to meet the one-month deadline for requesting deferral set out by Article 18(2) of the Statute. She wrote that “where a non-State party is involved, the principle of complementarity must be observed with particular rigour.”
Ibáñez Carranza also held that Israel’s Regulation 45 claim was central to its complementarity claim, and that the Prosecutor’s failure to inform the ICC Presidency that new referrals had been received post-October 7 prevented the Court from properly implementing its ensuing legal duties. The failure of the Pre-Trial Chamber to engage with this claim and to give reasons for its rejection of this part of Israel’s appeal “rendered the outcome of the Impugned Decision unreliable.” Hence, she would have remanded the question regarding the post-October 7 referrals to the Pre-Trial Chamber. She refrained from addressing the other grounds for challenge raised by Israel until this initial matter was resolved.
Judge Solomy Balungi Bossa, the second dissenting judge, was also of the view that given the significance of the post-October 7 referrals, the Pre-Trial Chamber erred in not addressing directly whether they gave rise to a new situation of crisis. Since she could not identify the legal basis on which this aspect of the lower decision was rendered, she also voted for remanding the case, and, like Judge Ibáñez Carranza, expressed no view on the other two grounds for challenge.
The most curious view is the concurring opinion of Judge Gocha Lordkipanidze. Although voting with the majority, he wrote that the Prosecutor should exercise due diligence and continuously assess whether an updated notification should be issued. Regular assessment “would strike a balance between two concomitant interests, on the one hand, providing a meaningful opportunity to a State to exercise its rights under Article 18(2) of the Statute and, on the other hand, ensuring the progression of the Prosecutor’s investigation without unwarranted interruption in accordance with the principles set out in the Court’s jurisprudence,” he wrote. Two factors are particularly relevant for the exercise of discretion, he averred: the lapse of time from the previous notification and diverging patterns and forms of criminality. He noted, in this regard, that new referrals may be indicative of such a divergence. He concluded with the following statement:
[I]n the specific circumstances of the present situation, no information has been placed before the Appeals Chamber that would compel the conclusion that the Prosecutor omitted to take the aforementioned factors into account in considering whether a new situation had arisen that would require a new notification under article 18(1) of the Statute to be issued. Should the Prosecutor, in a different scenario, arrive at the conclusion that changed circumstances give rise to a new situation upon receiving one or more referrals, he would be then duty-bound to decide whether to initiate an investigation into the new situation pursuant to articles 13(c), 14 and 53 of the Statute.
Complementarity and Mirroring
One notion that is completely missing from the Court’s decision on Israel’s Article 18 challenge is the concept of mirroring – the idea that a national investigation must be sufficiently comparable to a planned ICC investigation in order to render an ICC case inadmissible. Still, for a State to effectively mirror an ICC investigation, it needs a certain level of detail from the ICC about the scope and focus of the intended investigation. This concept appears to have been central to previous Article 18 cases issued by the ICC. In a 2023 judgment on complementarity in the Philippines case, the Appeals Chamber held that:
[F]or the purpose of admissibility challenges under article 18 of the Statute, a State is required to demonstrate an advancing process of domestic investigations and prosecutions of the same groups or categories of individuals in relation to the relevant criminality, including the patterns and forms of criminality, within a situation. The domestic criminal proceedings must sufficiently mirror the scope of the Prosecutor’s intended investigation (para. 106)
It further held that the Prosecutor’s Article 18 notification must include situation parameters that are sufficiently specific as to enable the Philippines to demonstrate “the degree of mirroring” – that is, a high level of comparability of domestic and ICC investigations.
In the same vein, in a 2024 judgment issued in the Venezuela case, the Appeals Chamber held with respect to crimes against humanity charges:
[I]f a State does not investigate the factual allegations underpinning the contextual elements of the alleged crimes against humanity that were sufficiently notified to it, it follows that it will not be able to demonstrate, in the proceedings under article 18(2) of the Statute, that the domestic criminal proceedings sufficiently mirror the scope of the Prosecutor’s intended investigation (para. 281).
The idea of “sufficient mirroring” is also mentioned in the OTP’s 2024 Policy Paper on Complementarity and Cooperation, noting that domestic proceedings should investigate “substantially the same conduct.”
We believe that it is against this standard (i.e., that complementarity depends on “sufficient mirroring”) that the Court’s approach to the specificity of the Article 18 notification and to the need to issue a new notification when the direction of the OTP investigation changes should be evaluated. The majority cited with approval the Venezuela decision in support of the proposition that the Article 18 complementarity test is whether the domestic investigation involved “the same groups or categories of individuals in relation to the relevant criminality, including the patterns and forms of criminality, within a situation.” Yet, it also cited with approval the same decision for the proposition that “there is no expectation at this stage of the proceedings that the Prosecutor should notify States of every act he or she intends to investigate, especially in those situations referred to the Court which cover a large number of alleged criminal acts,” and upheld “the Prosecutor’s prerogative to continue the investigation within the parameters of the Palestine Situation.”
It is generally accepted that the principle of complementarity operates as a balancing mechanism, designed to ensure that the Court’s legal powers do not excessively interfere with the sovereign right and legal interest of States to investigate serious crimes. As Judge Ibáñez Carranza correctly noted, such a balancing act should be applied with particular rigor when the rights and interests of non-member States are implicated. The principle of complementarity is also supported by practical considerations regarding the limited capacity of the Court and normative considerations regarding the many advantages of close-to-home legal proceedings. The centrality of the principle is manifested in the ICC Statute in that it involves an assessment of investigation mirroring at two separate points in time, at two different levels of precision: 1) at the investigation stage – “same group and categories of individuals” and “substantially the same conduct” or “patterns and forms of criminality” under Article 18; and 2) at the individual pre-trial or trial stage: same person/same conduct under Article 19 of the ICC Statute.
The Article 18 notification is intended to ensure that relevant States are put on alert that a full-fledged legal investigation of an international crime is about to take place before the ICC. The notification is intended to provide them with sufficient information that would allow them a reasonable opportunity to generate a mirroring domestic investigation at the Article 18 level of precision. This is why the Philippines judgment examined whether the notification was sufficiently specific. The need for a specific notification is therefore analytically separate from the question whether or not the new direction of the intended ICC investigation is tied to a new situation of crisis referred to the Court, or whether it is conducted under the same situation of crisis which gave rise to the previous notification. The critical test, in our view, is whether a previous notification is sufficiently specific to allow for a mirroring investigation. Put differently, the prerogative of the Prosecutor to expand an investigation into an existing situation, including into new events, is distinct from the ongoing duty – alluded to by Judge Lordkipanidze – to evaluate whether the change in direction requires a new notification that would facilitate mirroring at the domestic level.
It is difficult for us to see how, in the case of Israel, application of the majority’s approach effectively provided Israel with such a reasonable opportunity to generate a mirroring domestic investigation. As we have explained before, the 2021 notification and the related preliminary examination focused on three issues: West Bank settlements, hostilities in Gaza in 2014, and clashes on the Gaza border in 2018. It did not refer, obviously, to the sharp escalation of the armed conflict on and after October 7, nor did it invoke any crimes against humanity, or any of the specific patterns or forms of conduct for which arrest warrants were eventually sought – that is, starvation-related war crimes and crimes against humanity. While the Court is correct that the Prosecutor could have expanded the investigation, provided that he remained within the boundaries of the 2018 referrals, it fails to explain how Israel could generate a mirroring investigation without receiving more information of the specific conduct, and patterns and forms of criminality that the developing OTP investigation is planning to focus on.
Paying Only Lip Service to Complementarity
The Court’s refusal to engage with Israel’s post-October 7 investigative activity is also troubling. Only seven months passed between the start of the October 7 war and the Prosecutor’s request for arrest warrants. Yet, by August 2024, the IDF reported that 74 criminal investigations into potential crimes occurring during the war had already commenced and that more than 1,000 incidents were being examined by the IDF’s operational fact-finding assessment mechanism. Such investigative activity – which appears at first look to be extensive in scope – should have been reviewed under the Article 18 sufficient mirroring standard and compared to the (unnotified) specific parameters of the ICC’s post-October 7 investigation. This is particularly so, since Israel formally asked the Court on May 1, 2024, to defer the investigation, a request flatly rejected by the OTP for Israel’s failure to meet the one-month deadline established by the 2021 notification. This underscores our point: The OTP denied Israel a reasonable opportunity to claim that a mirroring investigation regarding post-October 7 policies and practices exists because Israel refrained from seeking a deferral in 2021 with regard to allegations involving pre-October 7 policies and practices.
This radical reading of complementarity as a one-off mechanism, impervious to changes in time, circumstances, patterns and forms of criminality, and domestic political and legal changes, does not represent, contrary to the Pre-Trial Chamber’s position, an approach that emanates from the “very object and purpose of the statutory complementarity framework;” rather, it entails the hollowing out of complementarity in the face of open-ended referrals and ongoing armed conflicts. In fact, the majority’s approach effectively confers unlimited power on the Prosecutor to proceed without notification to investigate any issue emanating from an open-ended referral of an ongoing armed conflict. The judgment broadly read the “defining parameters” of the 2021 notification – reading them together with the 2018 referral (despite the fact that referrals simply serve to authorize OTP investigations and delineate the outer limits of their scope, but not to determine what specific issues falling within the said scope would actually be investigated and would require a mirroring investigation). It cited with approval the Prosecutor’s position that it suffices, for the purpose of relying on a past notification, that the crimes occurred in the context of the same armed conflict. It also referred to the unprecedented events post-October 7 as “a continuity in pattern, even though a certain shift in circumstances.” The upshot of this approach is that a notification relating to one episode occurring in the beginning of an ongoing armed conflict, which is covered by an open-ended referral, would result in the loss of Article 18 complementarity for all subsequent episodes occurring later in the conflict (provided that the first notification did not lead to deferral).
The potential abuse of this approach manifests itself here. Israel did not, and could not realistically ask for a formal deferral in 2021 regarding settlement-related crimes, given its traditional opposition to Article 8(2)(8) of the ICC Statute and its ambiguous domestic law approach on the legality of settlements. This has no bearing, however, on Israel’s capacity to invoke complementarity with regard to other investigations actually launched by the OTP. The invocation of the earlier failure to obtain deferral in respect to one set of alleged war crimes (which as a non-member State it was not legally bound to do), for rejecting complementarity in respect of a very different set of war crimes and crimes against humanity occurring years later, appears to us unreasonable and running contrary to the basic tenets of the complementarity regime.
We note, in this regard, that Judge Lordkipanidze’s principled position on a case-by-case review of prosecutorial discretion is more reasonable than the one-off approach proposed by the OTP, which was implicitly endorsed by the other two majority judges. We do not understand, however, why after offering this approach, Lordkipanidze rejected Israel’s position. Given the passage of time from 2018 and 2021 to 2024, the dramatic shift in circumstances following the events of October 7, and the existence of new referrals, it is hard to justify a discretionary decision by the Prosecutor to deny Israel of its right to claim Article 18 complementarity – especially, given that the OTP did not cite any investigatory interests that would be seriously harmed by a new notification (and a one-month period allocated to respond to it by requesting a deferral – a request which the Court may accept or reject).
Although Israel (and Netanyahu and Gallant) may still claim before or at the commencement of the trial Article 19 complementarity – that is, that a domestic investigation of the same persons for the same conduct exists – the implications of barring Israel from invoking Article 18 are significant First, an article 18 deferral would have prevented the issuance of arrest warrants against the two Israeli leaders. Second, under Article 19, Israel also needs to meet a higher degree of mirroring. Hence, denying Israel Article 18 complementarity has real implications for the legal rights and interests of Israel and the two defendants.
A Long-Term Blow to the Court
The refusal of the ICC to effectively defend the rights of non-member States such as Israel, by denying them a reasonable opportunity to claim Article 18 complementarity, raises serious concerns about the Court’s commitment to the principle of complementarity. From a policy perspective, it is striking that the Court never explains how and why granting Israel another one-month period to claim complementarity under Article 18 would have derailed the OTP investigation in the Palestine case. Nor does it explain why, as a matter of general policy, issuing new notifications when “shifts in circumstances” occur would disrupt the mission of the Court and undermine its goal of ending impunity, a goal to whose implementation the principle of complementarity importantly contributes.
Instead, the majority adopted an interpretation of Article 18 that hollows out the principle as a practical matter. It adopted a most forgiving approach toward the Prosecutor’s failure to notify the Court’s Presidency of the new post-October 7 referrals (it considered its invocation by Israel as a “formal aspect.”). And although Judge Lordkipanidze offered a reasonable middle ground for addressing a change in circumstances, he never explained why the tests he proposed for OTP discretion did not apply to the case before him.
Significantly, the hollowing out of non-member States’ complementarity rights – by punishing them for not meeting a deadline in a treaty they never ratified – is reminiscent of the Court’s doubling down on the rejection of head of state immunity of non-member States, an issue that exceeds the scope of this note (see for a discussion here and here). In both cases, the Court is nominally operating within the ICC Statute framework but is prioritizing the Court’s prosecutorial power over the legal rights of non-member States under international law. Note, the Court is doing this while it is facing sanctions by third states for alleged jurisdictional over-reaches, and while the OTP is facing its worst-ever ethics crisis. Arguably, the future legitimacy of the Court is bound to suffer if it stays on this confrontational course.
To conclude, we consider complementarity to be a central pillar of the legal regime created by the ICC Statute. The Court’s failure to effectively protect this principle and to afford Israel, the deferral-requesting State, an opportunity to show that it is genuinely investigating allegations of deliberate starvation in Gaza, is not likely to increase support for the Court and its operations. Given all the controversy around the case and the OTP’s handling thereof, doubling down on an extremely narrow – and in our view, untenable – legal construction of the duty to notify under Article 18 does not bode well for the Court. The judgment is likely to further exacerbate the conflict between the Court and its powerful enemies, and further jeopardize its ability to operate (as the post-judgment sanctions imposed by the United States on members of the panel illustrate).
FEATURED IMAGE: The facade of the ICC building (via https://www.icc-cpi.int/about/the-court)