Since Israel’s military operations in Gaza began following the October 7 Hamas attack, reports of mass civilian casualties in Gaza have been met with a barrage of claim and counterclaim regarding attribution, responsibility, justification, and legality. Experts are concerned about the legality of certain attacks, even those involving civilian casualties, due to the lack of serious ground investigations. This confusion could lead to despair about the practical role of international humanitarian law in regulating hostilities during ongoing conflicts.
Taking into account Israel’s official statements regarding specific attacks allows an early assessment of the understanding of proportionality employed by the Israel Defense Forces (IDF) in their consideration of what may constitute “excessive” civilian deaths. The IDF’s disclosure of the military objective and attack means during the massive Oct. 31 Jabalia camp strike offers crucial insights into Israel’s approach to proportionality in Gaza hostilities.
A IDF spokesperson confirmed that the attack had been an Israeli airstrike, and within hours, the IDF published a press release stating that IDF fighter jets, acting on intelligence from the Israeli Security Agency (Shin Bet), had killed Ibrahim Biari, commander of Hamas’s central Jabalia battalion, described as one of the leaders of the Oct. 7 massacre. The Qassem brigades, Hamas’s military wing, dismissed the claim that a commander had been killed and accused Israel of targeting civilians. The IDF statement dismisses attribution and potential mistakes like target misidentification, pilot error, and weapon malfunction, stating the Oct. 31 Jabalia strike was a planned, planned attack on a known military target.
The killing of civilians is not necessarily unlawful under International Humanitarian Law (IHL), but it can be lawfully carried out if the harm is incidental to an attack on a military objective and the expected loss of civilian life, injury to civilians, damage to civilian objects, or a combination thereof is not excessive in relation to the concrete and direct military advantage anticipated. Israel and the U.S. both recognize the rule on proportionality in attack as a fundamental international law.
The test for proportionate killing of civilians is prospective, balancing foreseeable civilian harm and anticipated military advantage based on the knowledge available to a commander at the time. This means that proportionate killing of civilians is deliberate killing, even if IHL lawyers tend to be reticent on that point. Civilian harm is not the aim of the attack, but an outcome that was expected to be caused by the attack in the ordinary course of events. In addition to the general duty to spare civilians and take precautions to avoid or minimize civilian harm, a commander who knows or suspects that civilians will be present at the site of a planned attack on a military target is obliged to make an estimation of the expected civilian harm, known as collateral damage estimation (CDE). Only if the expected damage is proportionate (not “excessive”) can the attack lawfully be executed.
There has been renewed interest in the development of quantifiable or standardized methodologies for assessing proportionality, including artificial intelligence-assisted models. However, such models have been treated with suspicion, especially from humanitarians who understandably balk at the prospect of decreeing any level of civilian killing acceptable in advance.
Communicating proportionality limitations to commanders and their subordinates is a more immediate problem, as they need rules that can be operationalized efficiently and withstand the stress of battle. The U.S. and its allies and coalition partners in the wars in Afghanistan and Iraq developed the concept of the non-combatant casualty cut-off value (NCV) to address this problem. NCVs are classified and can be determined by a range of operational factors, both strategic and tactical, including the need to maintain public confidence.
ROEs are crucial for IHL compliance in operations, driven by a 2001 incident where a planned strike on Taliban leader Mullah Omar was abandoned due to the presence of four civilians at the attack site. The use of National Guard Vehicles (NCVs) was removed from U.S. military doctrine in 2018 following the largest urban battle since World War II, the siege of Mosul in 2016-17. The Pentagon’s Civilian Harm Mitigation and Response Action Plan published last year does not mention NCVs and outlines a more multifaceted approach to mitigating civilian harm. One main concern about NCVs was that setting an upper threshold for civilian casualties obscured the legal duty to avoid or minimize any civilian harm.
The Jabalia Camp Attack on October 31, 2023, was expected to cause significant civilian casualties due to the densely populated area of Jabalia, which had been previously targeted by Israel. Satellite visual analysis of the attack site showed at least five large craters, including two approximately 40 feet wide, consistent with the impact of 2,000-pound Joint Direct Attack Munitions. The attack destroyed not just one residential apartment building but a whole block.
Despite the expected civilian harm, the IDF would need to weigh the anticipated military advantage against this expected civilian harm. Amichai Cohen and Yuval Shany highlight the need for a comprehensive understanding of key assumptions underlying legal analyses of the 2023 Israel-Hamas War, as uncertainty remains regarding the assessment of each target’s military advantage.
The proportionality test for military advantage must be applied to individual attacks, and the military advantage must be both concrete and direct. The Israeli Defense Force (IDF) accepted a higher level of expected civilian casualties in the attack on Hamas in Jabalia compared to the US and UK’s operations against ISIS, with two justifications for this.
The IDF’s account of the collapse of buildings clarified that they struck “in between buildings, aiming to destroy the tunnels underneath” using large, precision-guided munitions. The result, bringing down nearby buildings, “cannot be avoided.” However, the estimation of civilian harm in the proportionality test includes the total harm reasonably foreseeable, which should include collateral damage expected from the collapse of the tunnels.
The IDF statement and comments also refer to IDF calls to residents to move south, but prior warnings are part of the law on precautions and cannot legitimate an otherwise unlawful attack. Israel’s responsibility for assessing proportionality is not affected by Hamas’s manifest failure to take passive precautions to protect civilians against attacks. Civilians who chose to remain in Jabalia retain their civilian status and protection under International Humanitarian Law (IHL) at all times.