In Defence of Preliminary Assessments: Proportionality and the 31 October Attack on the Jabalia Refugee Camp

Written by

Some international crimes require little information to spot, identify and characterize. Others are more difficult to discern because of unclear law, or a need for detailed factual information. While legal commentators can easily make determinations about the former, there is significant debate about the utility of making assessments about the latter during the conflict in Israel/Gaza. For example, a recent post on this blog seems to suggest that we should largely wait to make judgments because it is still ‘too early to tell’. In this post I explain why I disagree.

Specifically, in analysing the 31 October attack in the Jabalia Refugee Camp, Andreea Manea observes on the principle of proportionality that “[t]here is, as of yet, just not enough information available in the public domain in order to determine, with reasonable certainty, that the principle has been violated.” While I would like to stress that I found the post sensible and respectful, I disagree with the analysis and its implications. My disagreement hinges on the question of proportionality and engages with two issues: First, the strength of the case, and second, the amount of information needed to make preliminary assessments. Before discussing these questions, however, it should be noted that Luigi Daniele proposed in another recent post on this blog to view the attack through the lens of indiscriminate attack rather than pure proportionality. While I do not disagree with the core of his substantive argument, I do find the proportionality framework more fitting for the time being. This is because I cannot confidently remove the presumption that the Israel Defence Forces (IDF) were not effectively blind to discriminating between lawful military targets and civilians and civilian objects during the attack.

Degrees of certainty

Starting with the issue of the amount of information needed to make preliminary assessments, this question is essentially about degrees of certainty. In this regard, I find it useful to borrow frameworks from NGO- and UN Fact-finding missions. Based on a Geneva Academy report the standards applied range between ‘reasonable suspicion’, ‘balance of probabilities’, ‘clear and convincing evidence’, and ‘overwhelming evidence’. The report suggests that ‘balance of probability’ is the best starting point, and I find this reasonable also for preliminary legal commentary.

Strength of the case

On the issue on the strength of the case, I believe that we know quite a lot: We know the time of the attack, the place of the attack, the method of attack, the target, and we have significant information about the approximate civilian harm. This is not enough to make a judgment beyond reasonable doubt, but it is surely enough to make preliminary assessments.

The legal standard of most relevance is the Rome Statute’s definition of the war crime of disproportionate attacks. Article 8(2)(b)(iv) explains that an attack launched in the “knowledge” that the attack would cause “incidental loss of life or injury to civilians or damage to civilian objects” which would be “clearly excessive” when compared to the “concrete and direct overall military advantage anticipated” constitutes a war crime. This rule thus articulates the war crime of committing a serious violation of the underlying IHL prohibition against disproportionate attacks, as expressed in articles 51(5)(b) and 57(2)(a)(iii) of Additional Protocol I. The difference between a (mere) IHL violation and a war crime in this regard relates mainly to the mental element (the requirement of knowledge versus expectation) and the level of disproportion (clearly excessive civilian harm versus simply excessive civilian harm). As the charges made against Israel in relation to the Jabalia-attack generally relate to the commission of a war crime, I will focus on the war crime-standards articulated in the Rome Statute.

Now, what happened on 31 October 2023? An Israeli airstrike hit the densely populated Jabalia Refugee camp at around 2.30 pm local time in an attack that left several deep craters, levelled several buildings, and killed or injured a very large number of people. The attack was likely conducted using 2,000-pound bombs – so-called JDAMs, or Joint Direct Attack Munitions – meaning that these were very large bombs fitted with guidance kits. The reported numbers of killed or wounded vary, with the Palestinian authorities saying that close to 200 people were killed, while close to 800 people were wounded – although these numbers may cover more strikes. Others report lower numbers, but all count casualties, including deaths, in the hundreds. The IDF claims that the attack killed “dozens of Hamas operatives”, including the key target, senior Hamas commander Ibrahim Biari. Accordingly, even if we accept the smaller numbers and Israeli claims, hundreds of civilians were wounded or killed. Finally, to my knowledge no indication has been given by the IDF that the civilian losses were beyond what was anticipated.

From here, the question is how to utilize this information for legal analysis. I suggest the following: Firstly, in terms of the ‘knowledge’-requirement, we have clear information about the time and place of the attack, and the munitions used. We are also told that the attack was planned carefully. This gives us a basis for assessing the information available to the attacker. Secondly, in regard to the “[anticipated] concrete and direct overall military advantage”, we have explicit statements on the target of the attack. While these are not the same as the anticipated military advantage, they do provide useful information. As such, the stated aim was to kill a senior Hamas commander, Ibrahim Biari. This was featured as the single prominent element in an IDF press release, although other military benefits were also mentioned. While it can be difficult for outsiders to assess the importance of killing Biari, such statements indicate the reasoning behind the attack. Finally, the question of whether the expected civilian harm was “clearly excessive” hinges on the standards applied. I suggest the following: There is no objective standard, and we are plainly comparing apples and oranges. This means that some qualitative judgment has to be made. Here, the ‘reasonable military commander’-test asks us to consider reasonability in light of the type of person required to make the decision. Any such analysis, however, should be buttressed by considerations based e.g. on international practice.

International practice

Admittedly, we have very little to go on if we wish to base our understanding of proportionality on available case law. I suggest, however, that we do have valuable materials. Given that the attack was largely aimed at one man, the attack on Milan Martić discussed in the Gotovina case seems relevant. And given that the attack took place in an area with a high number of civilians present, an attack on a soccer match discussed in the Galić case should be considered.

In the former case, Croatian forces fired a number of artillery rounds at the apartment of Milan Martić and another location, where he was believed to be present. As commander in chief of the regional Serb forces, Martić was clearly an important and lawful military target, although the Trial Chamber referred to the advantage of targeting his apartment to disrupt his movements, communication, and command. On the issue of collateral damage, the Trial Chamber noted that both locations “were in otherwise predominantly civilian residential areas”, that at the time of firing “civilians could have reasonably been expected to be present”, and that the firing “created a significant risk of a high number of civilian casualties and injuries”. The Trial Chamber concluded that this risk was ”excessive in relation to the anticipated military advantage”. As the Appeals Chamber found errors in the 200-Metre Standard developed by the Trial Chamber to assess targeting, the accused were acquitted. This obviously limits the precedential value of the proportionality assessment. However, although this assessment was criticised by the Appeals Chamber, it was not specifically overturned. As noted by a dissenting judge, the assessment fell because of the overturning of the 200-Metre Standard, which had little to do with the attack on Martić. Indeed, the proportionality assessment was criticised mainly for not conducting a “concrete assessment of comparative military advantage” rather than for the standards applied.


In the Galić case the commander of the Sarajevo Romanija Corps was convicted for offenses related to the shelling and sniping campaign in Sarajevo. One aspect of the trial case was an incident where a soccer event was hit by mortar shells. While the attack was considered an example of indiscriminate shelling, the analysis contemplated proportionality. As such, the incident involved the shelling of an area where a soccer tournament was held and more than 10 people were killed and 100 injured. A significant number of the people present were soldiers. It was concluded that the attacking forces had not been informed about the event, but the Trial Chamber noted that had they been informed and intended to target the soldiers present, such an attack would have been unlawful. As the Trial Chamber explained: ”Although the number of soldiers present at the game was significant, an attack on a crowd of approximately 200 people, including numerous children, would clearly be expected to cause incidental loss of life and injuries to civilians excessive in relation to the direct and concrete military advantage anticipated.”

While neither of these cases are completely analogue to the Jabalia-attack and must be caveated in different ways, they do seem to provide a reasonable, approximate baseline for how an international court or tribunal might assess questions of excessiveness in the balance between expected civilian harm and anticipated military advantage.


With these considerations in mind, we can assess the present case. Namely, it seems highly likely that the expected civilian harm was anticipated to be massive – and likely much more severe that the civilian harm discussed in the two above cases. The actual deaths, injuries, and damages are indications thereof, especially given the lack of IDF-statements indicating otherwise. Using the phrasing of the Trial Chamber in the Gotovina case, the time, place, and method of attack surely “created a significant risk of a high number of civilian casualties and injuries”. The question then becomes if the expected military advantage, namely killing Biari, was correspondingly massive.

The IDF provided little concrete information in this regard, noting mainly that Biari was the Commander of Hamas’ Central Jabaliya Battalion, that he was “one of the leaders responsible” for the attack on 7 October 2023, and that he oversaw military operations in Northern Gaza. More generally, the IDF noted that the strike had “damaged Hamas’ command and control in the area, as well as its ability to direct military activities against IDF soldiers”. Although these are significant military advantages, they do not, in my view, come close to making a plausible case for proportionality. Note, for example, that the statement merely claims the attack “damaged” Hamas’ command and control and abilities rather than qualifying this using phrases like ‘severely damaged’, ‘extensively disrupted’, ‘effectively impeded’ etc. Indeed, although there are many specificities and differences in circumstances, the descriptions of Biari and the military advantage of the attack are not unlike those attached to Milan Martić and the military value in targeting him and his apartment. Accordingly, while the killing of a high-level Hamas leader can, of course, be considered a significant military advantage, it seems implausible that the advantage gained could be commensurate – in light of case law – to the reasonably expected civilian harm. Indeed, in a recent study on IHL proportionality it was convincingly argued that “planned attacks expected to cause extensive civilian damage may comply with the IHL proportionality rule only in cases where there is no other choice at all to attain a certain enormous military advantage.” I agree. And I find this attack to be an example where such extensive civilian damage seemed highly plausible, while a commensurate, enormous, expected military advantage seems highly implausible. Therefore, it would be reasonable to conclude, as a preliminary assessment, that the attack was not only disproportionate but constituted a war crime.

On a final note, I would like to stress that I share concerns about the many dubious legal claims made during this conflict. While we should be careful in our legal analyses and commentary, I find the attack in Jabalia Refugee Camp an exemplary case where legal assessments are justified and necessary. Indeed, with all the information available one could ask: If not here, then when?

Print Friendly, PDF & Email

Leave a Comment

Comments for this post are closed


Jackashley says

November 8, 2023

“ Note, for example, that the statement merely claims the attack “damaged” Hamas’ command and control and abilities rather than qualifying this using phrases like ‘severely damaged’, ‘extensively disrupted’, ‘effectively impeded’ etc. Indeed, although there are many specificities and differences in circumstances, the descriptions of Biari and the military advantage of the attack are not unlike those attached to Milan Martić and the military value in targeting him and his apartment. ”

The fact that at least part of this analysis turns on whether an IDF press release uses the word “damaged” or “severely damaged” kind of shows why these types of preliminary analyses are of such limited value. (Further, it doesn’t actually matter how much damage was done, it matters how much damage was anticipated )…

Jack ashley says

November 8, 2023

And the military advantage isn’t only the advantage of killing the commander. It’s the military advantage of gaining control of the camp and the Hamas command center, including recovering intelligence material contained in the command center like the map of tunnels they got, which has significant concrete military advantage, and whether this was anticipated.

We have no idea what they recovered from the command center (other than maps of Tunnels, which are extremely valuable).

Nobuo Hayashi says

November 9, 2023

Thank you, Marc, for this interesting post.

I nevertheless sense a degree of ambiguity about it in two respects. One concerns what law the ICTY applies v. what law the ICC applies. The other, which concerns the criminalisation of disproportionate attacks under customary ICL v. under the Rome Statute, is essentially an extension of the first.



The blog proposes to apply Article 8(2)(b)(iv) of the Rome Statute. It then goes on to base its preliminary assessment of the incident by reference to Gotovina and Galic.

I do not believe either of these cases applies the content of Article 8(2)(b)(iv). Rather, both Gotovina and Galic apply the customary content of Article 51(5)(b) of Additional Protocol I. There, the prohibition is against launching an attack that “may be expected” to cause excessively injurious incidental harm. The expectation concerns the collateral damage’s excessiveness, not the mere incidence of collateral damage.

As the blog correctly points out, Article 8(2)(b)(iv) raises the standard of criminalised disproportion on several grounds (e.g., excessiveness being “clear”). More importantly for our purposes here, Article 8(2)(b)(iv) requires that the perpetrator “knew” (“in the knowledge”) that the attack “will cause” excessive collateral damage. This resembles dolus directus of the second degree.

(See, for comparison, Article 30(2)(b) of the Rome Statute that provides the default intent requirement in relation to a consequence. The expression “was aware that [the consequence] will result in the ordinary course of events” is often interpreted to entail dolus directus of the second degree, or virtual certainty.)

Since both Gotovina and Galic apply the “may be expected to cause” standard of collateral damage’s excessiveness, their findings do not assist when interpreting the “knowledge that it will cause” standard we find in Article 8(2)(b)(iv).


What this also reveals is the need to distinguish between the war crime of disproportionate attacks under customary ICL (as applied by the ICTY), on the one hand, and the war crime of disproportionate attacks under Article 8(2)(b)(iv) of the Rome Statute, on the other.

As far as the ICTY case law is concerned, there is no difference between the IHL prohibition and the ICL criminalisation of disproportionate attacks. For the ICTY, both customary IHL and customary ICL use the content of Article 51(5)(b) of Additional Protocol I.

Article 8(2)(b)(iv) marks a clear departure from that approach. The switch from “may be expected to cause” to “knowledge that it will cause” excessive collateral damage is not accidental. The Rome Statute’s drafters intended to tighten the mental requirement for this offence. And, just to make sure it is crystal clear, those who drafted the third element of this offence even added footnote 37 that the knowledge of excessiveness “requires that the perpetrator make the value judgement as described” in that element. (NB: The footnote then cites the reasonable commander test when it observes: “An evaluation of that value judgement must be based on the requisite information available to the perpetrator at the time”.)


In other words, if, as the blog suggests, we are to preliminarily assess the incident based on Article 8(2)(b)(iv), we need information that tells us about what the attacker “knew” - more specifically, whether the attacker acted “in the knowledge that [his attack] will cause” excessive collateral damage. While it is entirely possible that we may come to the conclusion that, yes, he did indeed launch the attack in that knowledge, I would suggest that the legal standard proposed in the blog, i.e., that taken from Gotovina and Galic, is not the correct one to use in such a preliminary assessment.


Nicolas Boeglin says

November 9, 2023

Dear Professor Schack

Many thanks for this extremely accurate post.

It is not the very first time that war crimes are committed intentionnally by Israel military command.

May I refer you (and also our EJIL Talk colleagues) to UN report of 2014 israelian operation in Gaza in which we read that:

"671. Questions arise regarding the role of senior officials who set military policy in several areas examined by the commission, such as in the attacks of the Israel Defense Forces on residential buildings; the use of artillery and other explosive weapons with wide-area effects in densely populated areas; the destruction of entire neighbourhoods in Gaza; and the regular resort to live ammunition by the Israel Defense Forces, notably in crowd-control situations, in the West Bank. In many cases, individual soldiers may have been following agreed military policy, but it may be that the policy itself violates the laws of war.

672. The commission’s investigations also raise the issue of why the Israeli authorities failed to revise their policies in Gaza and the West Bank during the period under review by the commission. Indeed, the fact that the political and military leadership did not change its course of action, despite considerable information regarding the massive degree of death and destruction in Gaza, raises questions about potential violations of international humanitarian law by these officials, which may amount to war crimes".


Document A/HRC/29/CRP.4
available at

It seems that the very same policy is being implemented by IDF in Israel, causing the very same kind of damages. The difference between 2014 and 2023 being of course the intensity of bombing campaign initiated last October 7th on Gaza, and the major numbers with regard to Palestinian civilian population.

Yours sincerely

Nicolas Boeglin

Note: may I also refer you to a modest note on recent official reactions observed in Latin America last week (in French, sorry) available at:

Nicolas Boeglin says

December 9, 2023

Dear Professor Schack

May I add to my last comment what is indicated in last UN office of OCHA / OPT report on Gaza (to December 8):

"On 7 December, at about 15:50, thirty Palestinians were reportedly killed when a house was hit in Al Dorj neighbourhood, east of Gaza city;   

On 7 December, at about 21:40, 35 people were reportedly killed when two houses were hit in eastern Gaza city;

On 8 December, at about 8:15, 13 Palestinians were reportedly killed when a residential building was hit in An Nuseirat Camp, Middle Area;

On 8 December, at about 10:00, nine people were reportedly killed when a residential building was hit in western Khan Yunis. "


It seems quite clear that, in retaliation for the 7 October attack on its territory perpetrated by Hamas, Israel is committing the worst thing a State can commit: a collective punitive action against the civilian population of Gaza.

Yours sincerely

Nicolas Boeglin