Does the ICJ have the Legal Authority to Pronounce itself on the Right to Self-Defence?

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Jesse Lempel raises a profound issue in his recent post concerning the South African application for provisional measures against Israel in the Gaza genocide case. He asserts that the International Court of Justice, the principal judicial organ of the United Nations, cannot ‘order provisional measures that impair a state’s right to self-defence.’ The argument appears to be that the right to self-defence is an ‘inherent’ attribute of states according to Article 51 of the Charter. Hence, the application of the right rests entirely with the state invoking it. For the Court to restrict that entitlement would be a violation by the Court of the UN Charter.

This view exposes the tension between two values reflected in the international system. On the one hand, there is the neo-classical right of the state to preserve itself from external harm. The state, it is argued, must remain free to take the action it judges necessary in order to safeguard its own existence. On the other hand, there is the modern view. This view focuses on the interests of the international system as a whole. This includes the interest in maintaining a credible prohibition on the use of force. This in turn requires the imposition of limits to claims to self-defence put forward by states.

Defence of the State or Defence of the System?

Classical international law offered a broad right of ‘self-preservation’ to states, including the right to use force in pursuit of claims or interests. The absolute view on sovereignty meant that no institution could pronounce itself on such claims, as there was no higher authority than the state.

It was the catastrophe of the first Great War that forced a revolutionary change. The League of Nations Covenant recognized in Article 11 that matters of war and peace are ‘a matter of concern of the whole League,’ rendering a failure to comply with the Covenant ‘an act of war against all other members of the League.’ [Article 16]. Hence, the system as a whole took on an identity of its own. Preserving its key rules would preserve the territorial integrity and independence of member states while also helping to preserve the system as such.

The failure of the League was answered with the design of the United Nations system which emphasized effective preventative action to ensure a warless world. The ‘inherent right of individual or collective self-defence’ was included in Article 51 of the Charter.

The ‘Inherent’ Right of Self-defence

The word ‘inherent’ (and its French translation) was taken by some early interpreters of the UN Charter as confirmation of the classical view that self-preservation of the state is a natural right inherent in statehood, and thus ‘impresciptable’ and beyond positive codification. The immutable character of that right seemed to be confirmed by the wording of Article 51, providing that ‘nothing shall impair’ the inherent right of self-defence. However, it soon became clear that the inherent right to self-defence is not the absolute right to self-preservation of previous ages. Instead, the inherent right to individual and collective self-defence that remains unimpaired by the UN Charter is the right as defined in Article 51. There would be no point to offering a definition of the content of the right to self-defence in Article 51, if that article were taken to assert at the same time that self-defense is in fact beyond codification.

Self-defence as Defence of the System

Of course, the state under armed attack remains the beneficiary of the right to self-defence. However, in defending itself, the state is also defending the jus cogens rules on the non-use of force. It is acting as an agent of the international constitutional system in ensuring compliance with rules of fundamental interest to the international system as a whole—the famous dedoublement foncitionnel already identified by George Scelle in 1932.

The UN Charter design, which places Article 51 expressly in Chapter VII on collective security, is very clear in stating that self-defence is a provisional right that only applies until the Security Council can take over from the defending state by adopting the collective measures necessary for the maintenance of international peace and security.

According to Article 51, the right of self-defence—however inherent in the legal personality of the state it may be—’shall not in any way affect the authority and responsibility’ of the Council. The primacy of the Council includes the authority to confirm that self-defence applies in individual instance (9/11, Resolution 1368 (2001)), it can determine which party is entitled to self-defence (Korea, Resolutions 83 (1950), 84 (1950)) and it can confirm that the right continues to apply even if the Council has taken some collective measures (Kuwait, Resolutions 661 (1991), 665 (1991)).

Suspending or Terminating Self-defence?

The Council can also determine that self-defence is not, or is no longer, available as the original armed attack has ceased. Its threat to exercise this power helped terminate the Iran-Iraq war of 1980 when the end of the first Cold War unblocked the system of collective security for a while.

Of course, it is more difficult to judge when the Council has taken sufficient enforcement action, leading to a suspension of the right to self-defence according to Article 51. Some scholars, for instance, Yoram Dinstein, assert that only the affected state itself can determine that the action of the Council is sufficiently effective to suspend self-defence. After all, its very survival as a state may be at issue.

The 19th century view that the survival of a state may be the ultimate value in the international system received an unexpected boost in the ICJ Advisory Opinion on Nuclear Weapons. [ICJ Rep 1996, p. 222, paras 95, 105] In a somewhat obscure passage, the Court seemed to suggest that international law, including essential rules of humanitarian law, may not apply as they would otherwise do, where a state is confronted with an extreme circumstance of self-defence. This has been rightly described as a ‘dangerous confusion.’ However, a member of the Court clarified that the intention had not been to elevate self-defence over other high status rules of international law. Rather, the need to deter an attack with weapons of mass destruction necessitated this reference. [Judge Fleischhauer, id., Separate Opinion, p. 305, para 6.]

It may be said that all of this is rather hypothetical. The veto has mainly prevented the Council from acting with sufficient vigour to allow an argument that it has now adopted the ‘measures necessary.’ But this fact is not relevant to the question of whether or not a collective body has the authority to suspend or terminate the application of the ‘inherent’ right to self-defence. Clearly, at least the Security Council has that authority in principle, even if rarely exercised thus far.

Is there a Role for the ICJ?

The question is whether the ICJ also has a role to play, in this instance through the application of provisional measures? The tension here lies in the fact that the Security Council exercises ‘primary responsibility for international peace and security.’ [UN Charter, Article 24 (1).] On the other hand, the ICJ is the ‘principal judicial organ’ of the United Nations [Article 92]. Does the function of the former exclude the function of the latter in relation to self-defence? Or could it be that there is a division of tasks. While the Security Council would exercise a political function, given its emphasis on effective action to maintain or restore peace, the Court would act as guardian of the legal limits of claims to self-defence.

Matters of High Policy and the Use of Force

The ICJ has consistently refused the argument that it cannot decide a case because the dispute has strong political dimensions. [E.g., Aegean Continental Shelf (Greece/Turkey), Jurisdiction, 1978, 3, 13; Tehran Hostages, ICJ Rep. 1980, 3, 20]. The Court has noted repeatedly that ‘whatever its political aspects, the Court cannot refuse to admit the legal character of a question which invites it to discharge an essentially judicial task.’ [Quoted with a range of further authority in the Wall Opinion on Israel/Palestine, ICJ Rep 2004, p. 46, para 41]

Moreover, the same logic has been applied to disputes involving even ‘serious’ uses of force:

It must also be remembered that, as the Corfu Channel case (I.C.J. Reports 1949, p. 4) shows, the Court has never shied away from a case brought before it merely because it had political implications or because it involved serious elements of the use of force. [Nicaragua, Jurisdiction, ICJ Rep 1984, p. 392, para 96]

In fact, the Court has addressed a significant string of cases involving the use of force, including, in addition to Corfu Channel and Nicaragua, Transborder Armed Actions, Platforms, the Armed Activities cases, the Bosnia and Croatia Genocide cases, the Discrimination case between Armenia and Azerbaijan, litigation concerning Georgia and the Russian Federation and Ukraine and the Russian Federation, plus important Advisory Opinions, like Nuclear Weapons and the Wall.

Competition with the Security Council?

A somewhat different variant of this argument would assert that the ICJ cannot become active in relation to issues concerning international peace and security addressed by other UN bodies, or at least the UN Security Council. Hence, it is sometimes argued, that where the Security Council is seized with an issue, the ICJ must respect the role of the Council and remain silent.

However, in the Nicaragua case, the Court emphasized that the primary role of the Council did not mean that it had an exclusive role to play:

The Charter accordingly does not confer exclusive responsibility upon the Security Council for the purpose. For a clear demarcation of functions between the General Assembly and the Security Council, in respect of any dispute or situation, that the former should not make any recommendation with regard to that dispute or situation unless the Security Council so requires, there is no similar provision anywhere in the Charter with respect to the Security Council and the Court. The Council has functions of a political nature assigned to it, whereas the Court exercises purely judicial functions. Both organs can therefore perform their separate but complementary functions with respect to the same events. [Nicaragua, Jurisdiction, ICJ Rep. 1984, p. 392, para 95]

Matters decided under Chapter VII

This liberal approach even extends to the final, and perhaps strongest possible argument cautioning against ICJ involvement in certain cases. These are instances where the Security Council has taken decisions addressing threats to the peace, breaches of the peace, or acts of aggression (mainly, although not necessarily exclusively, formal action under Chapter VII). It could be argued that legal action by the Court could question or prejudice political action by the Council in such cases. This argument was pursued with some vigour in the context of attempts to attack the arms embargo against Bosnia through the Court while that country was confronted with a campaign of ethnic cleansing and genocide. [See Bosnian Genocide Case, Judge Lauterpacht, Separate Opinion, ICJ Rep 1993, p 326, 407, paras 98ff]

Again, though, actual practice over many decades runs against this argument. The Court has not only interpreted the legal character and force of Security Council resolutions (e.g., Namibia Opinion [ICJ Rep 1971, p 16, paras 52ff]) and pronounced on their content [for instance, Kosovo Advisory Opinion, ICJ Rep 2010, p. 403, para 94], but it has also pronounced itself on their validity [Namibia, above, para 20ff]. In the Judgment on Jurisdiction in the Lockerbie case, the Court did not accept the argument that the case could no longer be addressed, given the adoption of Chapter VII Resolution 748 which, it had been asserted, was henceforth controlling the issue under review. [Lockerbie, Jurisdiction, ICJ Rep 1998, p. 9, paras 44ff] In the Armed Activities Case (DR Congo-Uganda), among the several others already noted above, the ICJ considered a use of force case that had been addressed by the UN Security Council and ordered interim measures in relation to it. [ICJ Rep 2000, p. 111, para 47]

This view is fully in accord with the changing understanding of the role of the Security Council after the (as it turned out, provisional) termination of the Cold War around 1990. There was a sudden plethora of Charter VII decisions entirely unforeseen at the time of the drafting of the Charter. This covered items like the creation of international criminal tribunals, establishing mechanisms for the award of compensation, cooperation in addressing terrorism, the administration of sanctions against individuals, the establishment of boundary demarcation bodies, provision for disarmament and the prevention of proliferation of weapons, potentially even the environment, etc. Such quasi-legislative and quasi-judicial activism would not have been possible or acceptable had it taken place in a legal vacuum, without the prospect of possible legal assessment of Council actions by the ICJ.

No Chapter VII Resolution on Gaza

Of course, in this instance, the UN Security Council has been unable to act with reference to Chapter VII. When confronted with the repeated application of the US veto, the Council was only able, eventually, to adopt resolutions without such a reference, addressing humanitarian issues and not the ius ad bellum (Resolutions 2712 (2023), 2720 (2023)).

While these texts at times adopt mandatory language (‘demands’), they are not formally adopted under Chapter VII. There is no finding of a threat to the peace, breach of the peace or act of aggression, and no invocation of Chapter VII or of Articles 40, 41 or 42. In Council practice since 1991, starting with Resolution 688 (1991), these two elements are taken as reliable indicators of the Chapter VII character of a text.

Hence, there is actually no prospect of supposed interference by the ICJ with matters decided by the Council under Chapter VII. Even if there had been a Chapter VII resolution, it would not likely have addressed the question of self-defence. In fact, the refusal to include a reference to Israel’s claimed right to self-defence contributed to the US decision to veto several earlier attempts to pass a resolution on the conflict in Gaza.

Non-justiciability of Self-Defence?

Hence, the ICJ can address issues concerning the use of force, including those also addressed by the Security Council. The question remains whether there is any reason to go against this finding where a case involving self-defence is concerned.

Starting with the Nicaragua litigation as far back as the 1980s, the ICJ has addressed a whole series of contentious cases involving the use of force (above). As self-defence is the principal justification for the use of force available to states, virtually all of these turned on arguments of self-defence. In Nicaragua, the Court expressly held:

As to the inherent right of self-defence, the fact that it is referred to in the Charter as a “right” is indicative of a legal dimension; if in the present proceedings it becomes necessary for the Court to judge in this respect between the Parties – for the rights of no other State may be adjudicated in these proceedings – it cannot be debarred from doing so by the existence of a procedure for the States concerned to report to the Security Council in this connection. [Nicaragua, Jurisdiction, ICJ Rep. 1984, p. 392, para 98]

Other judicial bodies have done the same [E.g., Ethiopia/Eritrea, Partial Award, Jus ad Bellum, Ethiopian Claims 1-8, passim] Similarly, the ICJ has considered self-defence in some detail in its advisory opinions, in particular the Nuclear Weapons Opinion. Indeed, it has had no hesitation to address the issue of self-defence in relation to Israel in the Wall Opinion, although it found that the concept did not apply in that instance. [ICJ Rep 204, p. 136, paras 138-142]

No Grounds for a Bar to Provisional Measures

If the Council has the authority to review issues concerning the use of force, and if it can pronounce itself on self-defence, then it is not easy to see how a bar to adopting provisional measures can be constructed in those instances. In fact, it has had no hesitation in the past to adopt interim measures of protection where the use of force and claims to self-defence are concerned. [E.g., Armed Activities, Congo-Uganda, ICJ Rep 2000, p. 111, para 47]

Most recently, in relation to Ukraine, the Russian Federation had offered an, admittedly, somewhat confused legal justification for the invasion to the UN Security Council, also drawing on self-defence. In that instance, the Provisional Measures Order formally requires the Russian Federation to ‘immediately suspend the military operation that it commenced on 24 February 2022 in the territory of Ukraine.’ [ICJ Rep 2022, p. 211, para 86] This does amount to a suspension of the claimed right to self-defence, along with the rejection of other supposed justifications offered by the Russian Federation.

It is of course true that Israel, in contrast to Ukraine, suffered an atrocious attack before launching the present operations in Gaza. This will likely affect the appreciation of Israel’s position on self-defence on the part of the Court if it comes to that.

Given the jurisdictional focus and certain other factors in the present case, the Court may of course be reluctant to stray too far into jus ad bellum issues, if it addresses them at all, although it did so in relation to Ukraine. After all, genocide, if it is found to be occurring in Gaza, would be fundamentally unlawful, whether or not self-defence applies. However, contrary to Jesse Lempel’s spirited argument, Israel cannot avoid scrutiny of its use of force and associated practices, and possible interim measures of protection, simply by invoking self-defence. The use of force by one state, whatever the justification offered, is a matter of concern for the organized international community as a whole. Cases of this nature can be addressed by the competent international institutions, including the ICJ, through all the legal instruments at their disposal.

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Jesse Lempel says

January 10, 2024

Dear Professor Weller: Thank you for your post engaging with mine. I fear, however, that your post has profoundly misunderstood my argument and largely knocks down a strawman.

Contrary to your characterization, I did not argue that the issues of self-defense are non-justiciable or that "the application of the right rests entirely with the state invoking it." Nor did I argue that Israel can "avoid scrutiny of its use of force and associated practices, and possible interim measures of protection, simply by invoking self-defence." And my argument does not turn in any way on Article 51's use of the word "inherent" or on any perceived competition between the ICJ and the Security Council.

The argument I outlined in my post is much simpler: that the ICJ's authority to indicate provisional measures is a creature of the UN Charter and therefore must comport with the Charter's own limitations, including Article 51. Do you disagree with that proposition as a general matter?

(Your post seems to rely on Ukraine v. Russia in support of the notion that the Court can issue provisional measures that "amount to a suspension of the claimed right to self-defence." I do not think that the ICJ decided this question there, for the reasons given in my comment addressed to Professors Milanovic and van Steenberghe under my blog post. To the extent you suggest that the ICJ's order should be read as implicitly rejecting Russia's Article 51 argument, then the Ukraine case would hardly contradict my assertion that the Court must ensure that its provisional measures comport with Article 51.)

My post acknowledges that there is an important and vigorous debate whether Israel's military action in Gaza is properly analyzed under the Article 51 framework. I do not believe I made an original contribution to that specific debate, but rather pointed out how -- if Article 51 does in fact apply, or if the Court deems it prudent at this stage to assume without deciding that Article 51 applies -- that assumption should affect the scope of provisional measures available to the Court.

Of course, the Court could, if it decides it has jurisdiction to reach these issues, conclude that Article 51 does not apply or that any specific order it issues is consistent with Article 51. I have no disagreement with you that evaluating the applicability and lawfulness of a State's claimed self-defense is generally within the Court's competence. What the Court cannot do, in my opinion, is indicate provisional measures that are inconsistent with Article 51 -- i.e., that impair the lawful exercise of the right of self-defense.

My post also expressly acknowledges that "Article 51 only goes so far" and that "[t]here are limits to self-defense." Again, should the ICJ reach these issues, it could decide that Article 51 does not apply here or that any order it issues is consistent with the lawful exercise of Article 51. But I also believe that it would be unwise to fully adjudicate these thorny issues in this rushed, interim procedural posture.

That is why I suggested in my post that, if the Court decides to "order Israel to refrain from specific combat activities, it should add the caveat: 'except as necessary to lawfully exercise the right of self-defence recognized in Article 51 of the Charter.'"


David Rosen says

January 11, 2024

Thank you for this contribution, Professor Weller.

It seems to me that one issue that has not been fully addressed in this piece, and which is quite critical to Mr Lempel's argument, is the limited function being performed by the Court when indicating provisional measures. It can hardly be doubted that if Israel invokes Article 51 in its arguments on the merits of the case, the ICJ could 'pronounce itself' on self-defence in its final decision.

However, the analysis of Israel's invocation of Article 51 is likely to be complex, involving difficult questions of fact and law contested both between the parties and other interested States. In considering whether to indicate provisional measures, the Court does not have the benefit of proper submissions or evidence on the question of self-defence and it would, in my view, be quite inappropriate to express any definite view on that question in these circumstances. This is why Mr Lempel's argument that the Court should assume, for the purpose of framing its provisional measures, that Israel may have validly invoked Article 51 of the Charter is quite compelling. The Court is not currently in a position to fairly proceed in any other way.

Alternatively, the Court should at least frame the provisional measures in a manner that acknowledges that Israel retains a right to self-defence, without prejudice to the question of whether that right is actually implicated in the current situation.

Ahmed Khafagy says

January 11, 2024

Dear Professor Weller,

Thank you for your blog, I just to give some reflections. First; the argument that Israel will use before the ICJ of the right of self defense according to Article 51 of the UN Charter is under thorough scrutiny in light of that Gaza Strip is still under occupation despite the withdrawal of the Israeli troops in 2005. Israel exercises control over the airspace, territorial waters, land crossings, water, electricity and civilian infrastructure in Gaza. In addition, When IDF troops withdrew from Gaza, Israel did not declare officially that It ended its occupation to Gaza.
Second; I do not see that the provisional measures overlap the function of the Security Council, I see them complimentary. The US was against any resolutions to cease fire in Gaza despite the massive destructions happening in Gaza and reports of Genocide and war crimes. I can see that the General Assembly issued two resolutions ( the second with 153 Country votes)calling for cease fire where the work of the GA does not overlap or contradict with the work of the Security Council, both the GA and the ICJ are main organs of the UN. Late Judge Crawford said and I quote" Provisional Measures before International Courts and Tribunals is a reflection of the growing maturity of the system of international courts and tribunals and their procedure". We need to support the rising use of the provisional measures as an evolution to the International Law.
Third; What matters here that the provisional measures requested by South Africa are based on solid grounds amid allegations of Gencoide crimes committed by the IDF in Gaza supported by specific intent 'dolus specialis' where we have so many statements of intent by Israeli State officials and others to commit and persist in committing genocidal acts or fails to prevent them in Gaza since October 7, 2023.
Thank you.