The following questions and answers address issues relating to international humanitarian law (the laws of war) governing the armed conflict between Israel and Hamas, Islamic Jihad, and other Palestinian armed groups in Gaza that took place from May 10 to May 21, 2021. The purpose is to facilitate analysis of the conduct of all parties to the conflict with the aim of encouraging accountability for violations of the laws of war and avoiding repetition in the future.
This Q&A focuses on international humanitarian law governing the conduct of hostilities by each party to the conflict. It does not address whether the armed wings of Hamas, Islamic Jihad, and other Palestinian armed groups or the Israeli government were justified in resorting to armed force, such as under the United Nations Charter. In accordance with our institutional mandate, Human Rights Watch maintains a position of neutrality on these issues of jus ad bellum (law concerning acceptable justifications to use armed force); our primary goal is documenting violations of, and encouraging all sides in armed conflicts to respect, the laws of war, or jus in bello (law concerning acceptable conduct in war). The May 2021 conflict followed rising tensions in Jerusalem, including from efforts by Jewish settler groups to evict and confiscate the property of long-time Palestinian residents from their homes in the Sheikh Jarrah neighborhood of East Jerusalem, which Israel unilaterally annexed but remains occupied territory under international humanitarian law. In addition, Palestinians held demonstrations around East Jerusalem, and Israeli forces fired teargas, stun grenades, and rubber-coated steel bullets, including inside al-Aqsa Mosque.
Palestinian demonstrators at times threw rocks during confrontations with Israeli security forces. The confrontations in East Jerusalem injured hundreds of Palestinians between May 7 and May 10, according to the United Nations Office for the Coordination of Humanitarian Affairs (UN OCHA).
On May 10, Palestinian armed groups in Gaza started to launch rockets towards Israeli population centers. The Israeli military attacked targets within the densely populated Gaza Strip with missiles, rockets, and artillery.
A ceasefire between the warring parties went into effect on May 21 at 2 a.m. local time.
According to the UN OCHA as of May 25, the fighting had resulted in the killing of 253 people in Gaza, including 66 children. Rockets launched from Gaza into Israel by Palestinian factions killed 12 people, including 2 children.
As of May 20, according to UN OCHA, Israeli forces had killed 25 Palestinians and injured 6308, including 84 children, during confrontations between Israeli forces and Palestinian protesters – who often threw rocks at them – in the West Bank, including East Jerusalem.
1. What international humanitarian law applied to the May 2021 fighting between Israel and Hamas?
2. Who and what is subject to military attack?
3. What were the obligations of Israel and Hamas with respect to fighting in populated areas?
5. What are the legal protections for hospitals, medical personnel, and ambulances?
6. Was Israel permitted to attack mosques or schools in Gaza?
7. Was Hamas’s firing of rockets at Israel lawful?
8. Was it lawful to target leaders of Hamas and their offices and homes?
9. What is meant by “collective punishment” of the civilian population?
10. Do journalists have special protection from attack?
12. What are Israel’s and Hamas’s obligations to humanitarian agencies?
13. Who can be held responsible for violations of international humanitarian law?
15. What other venues for accountability exist?
The armed conflict between Israel and Hamas and other Palestinian armed groups from May 10 to May 21, 2021, was governed by international treaty law, most notably Common Article 3 to the Geneva Conventions of 1949, and the rules of customary international humanitarian law, which are reflected in the Additional Protocols of 1977 to the Geneva Conventions. These rules set forth minimum standards for all parties to an armed conflict, both states and non-state armed groups.
Foremost among the laws of war is the rule that parties to a conflict must distinguish at all times between combatants and civilians. Civilians may never be the deliberate target of attacks. Warring parties are required to take all feasible precautions to minimize harm to civilians and civilian objects. Attacks may target only military objectives. Attacks targeting civilians or that fail to discriminate between combatants and civilians, or would cause disproportionate harm to the civilian population compared to the anticipated military gain, are prohibited.
The laws of war limit permissible means and methods of warfare by parties to an armed conflict and require them to respect and protect civilians and captured combatants. The fundamental tenets of this law are “civilian immunity” and the principle of “distinction.” While the laws of war recognize that some civilian casualties may be inevitable during armed conflict, they impose a duty on warring parties at all times to distinguish between combatants and civilians, and to target only combatants and other military objectives.
Combatants include members of a country’s armed forces and commanders and fighters in non-state armed groups. They are subject to attack at all times during hostilities unless they are captured or incapacitated. Civilians lose their immunity from attack when and only for such time as they are directly participating in hostilities. According to the International Committee of the Red Cross, the laws of war distinguish members of the organized fighting forces of a non-state party, who may be targeted when there is fighting, from those who assume exclusively political, administrative, or other non-combat functions, who may not be targeted even when there is fighting. An individual recruited, trained, and equipped by a non-state armed group is considered integrated into that group even before carrying out a hostile act at a time of fighting. Such fighters who leave the armed group, as well as regular army reservists who reintegrate into civilian life, are civilians until they are called back to active duty.
As discussed below, mere membership or affiliation with Hamas, which is a political entity with an armed component, is not a sufficient basis for determining an individual to be a lawful military target. Israel’s labeling of certain individuals as “terrorists” does not make them military targets as a matter of law unless they meet the above-noted definition of a combatant, so attacks on such persons may be unlawful attacks on civilians.
The laws of war also protect civilian objects, which are defined as anything not considered a legitimate military objective. Prohibited are direct attacks against civilian objects, such as homes and apartments, places of worship, hospitals and other medical facilities, schools, and cultural monuments – unless they are being used at the time for military purposes and meet the standards outlined below. Civilian objects become subject to legitimate attack when they become military objectives – that is, when they are making an effective contribution to military action and their destruction, capture, or neutralization offers a definite military advantage, subject to the rules of proportionality outlined below. This would include the presence of members of armed groups or military forces in what are normally civilian objects. Where there is doubt about the nature of an object, it must be presumed to be civilian.
The laws of war prohibit indiscriminate attacks. Indiscriminate attacks are of a nature to strike military objectives and civilians or civilian objects without distinction. Examples of indiscriminate attacks are those that are not directed at a specific military objective or that use weapons that cannot be directed at a specific military objective. Prohibited indiscriminate attacks include area bombardment, which are attacks by artillery or other means that treat as a single military objective a number of clearly separated and distinct military objectives located in an area containing a concentration of civilians and civilian objects.
An attack on an otherwise legitimate military target is prohibited if it would violate the principle of proportionality. Disproportionate attacks are those that may be expected to cause incidental loss of civilian life or damage to civilian objects that would be excessive in relation to the concrete and direct military advantage anticipated from the attack.
Gaza is one of the most densely populated areas in the world. International humanitarian law does not prohibit fighting in urban areas, although the presence of many civilians places greater obligations on warring parties to take steps to minimize harm to civilians.
The laws of war require that the parties to a conflict take constant care during military operations to spare the civilian population and to “take all feasible precautions” to avoid or minimize the incidental loss of civilian life and damage to civilian objects. These precautions include doing everything feasible to verify that the objects of attack are military objectives and not civilians or civilian objects, giving “effective advance warning” of attacks when circumstances permit, and refraining from an attack if the rule of proportionality will be violated. In populated areas with buildings or other structures, both above and underground, parties should take into account the difficulty of identifying civilians who may be obscured from view even from advanced surveillance technology.
Forces deployed in populated areas must, to the extent feasible, avoid locating military objectives – including fighters, ammunition, weapons, equipment, and military infrastructure – in or near densely populated areas, and endeavor to remove civilians from the vicinity of military objectives. Belligerents are prohibited from using civilians to shield military objectives or operations from attack. “Shielding” refers to purposefully using the presence of civilians to render military forces or areas immune from attack.
At the same time, the attacking party is not relieved from its obligation to take into account the risk to civilians, including the duty to avoid causing disproportionate harm to civilians, simply because it considers the defending party responsible for having located legitimate military targets within or near populated areas. That is, the presence of a Hamas commander or rocket launcher or other military facility in a populated area would not justify attacking the area without regard to the threatened civilian population, including the duty to distinguish combatants from civilians and the rule of proportionality.
The use of explosive weapons with wide-area effects in populated areas, often referred to as EWIPA, is one of the gravest threats to civilians in contemporary armed conflict. In addition to causing civilian casualties directly, explosive weapons with wide-area effects have frequently damaged or destroyed civilian infrastructure, such as bridges, water pipes, power stations, hospitals, and schools, causing long-term harm to civilians, including the disruption of basic services. These weapons have a wide-area effect if they have a large destructive radius, are inherently inaccurate, or deliver multiple munitions at the same time. Their use in populated areas forces people to flee their homes, exacerbating humanitarian needs.
Weapons that have a large destructive radius include those that detonate a large amount of explosive material and those that propel fragments over a large area, or both. Munitions with large amounts of explosive material can produce fragmentation that spreads unpredictably over a wide-area and a powerful blast wave that can cause severe physical injuries to the human body and physical structures, cause blunt force trauma and physical damage from flying debris, and cause or exacerbate other injuries or existing illnesses. Munitions that have pre-formed fragmentation warheads are designed to spread scores of fragments over an area, making it difficult or impossible to limit the effects of the weapon.
The use of explosive weapons with wide-area effects in the densely populated Gaza Strip, where more than two million Palestinians live in a strip of territory that is 41 kilometers long and between 6 and 12 kilometers wide, and the targeting at times of critical infrastructure, could be expected to cause serious harm to civilians and civilian objects. In addition, the rockets launched from Gaza that were fundamentally inaccurate or designed to saturate a large area and were likely to strike civilians and civilian objects inside Israel, also constitute explosive weapons with wide-area effects.
On some occasions during Israeli attacks on Gaza between May 10 and May 21, Israeli forces issued purported warnings of attacks to affected civilians in Gaza. These took the form of small “knock on the roof” attacks (carried out with small air-delivered munitions) or messages conveyed by telephone, including phone calls to building residents.
The laws of war require, unless circumstances do not permit, that warring parties give “effective advance warning” of attacks that may affect the civilian population. What constitutes an “effective” warning will depend on the circumstances. Such an assessment would take into account the timing of the warning and the ability of the civilians to leave the area. A warning that does not give civilians adequate time to leave for a safer area would not be considered “effective.”
Civilians who do not evacuate following warnings are still fully protected by international law. Otherwise, warring parties could use warnings to cause forced displacement, threatening civilians with deliberate harm if they did not heed them. Moreover, some civilians are unable to heed a warning to evacuate, for reasons of health, disability, fear, or lack of anyplace else to go. So, even after warnings have been given, attacking forces must still take all feasible precautions to avoid loss of civilian life and property. This includes canceling an attack when it became apparent that the target is civilian or that the civilian loss would be disproportionate to the expected military gain.
The laws of war also prohibit “acts or threats of violence the primary purpose of which is to spread terror among the civilian population.” Statements that called for the evacuation of areas that are not genuine warnings, but are primarily intended to cause panic among residents or compel them to leave their homes for reasons other than their safety, would fall under this prohibition. This prohibition does not attempt to address the effects of lawful attacks, which ordinarily cause fear, but rather those threats or attacks on civilians that have this specific purpose.
Healthcare facilities are civilian objects that have special protections under the laws of war against attacks and other acts of violence including bombing, shelling, looting, forced entry, shooting into, encircling, or other forceful interference such as intentionally depriving facilities of electricity and water.
Healthcare facilities include hospitals, laboratories, clinics, first-aid posts, blood transfusion centers, and the medical and pharmaceutical stores of these facilities, whether military or civilian. While other presumptively civilian structures become military objectives if they are being used for a military purpose, hospitals lose their protection from attack only if they are being used, outside their humanitarian function, to commit “acts harmful to the enemy.” Several types of acts do not constitute “acts harmful to the enemy,” such as the presence of armed guards, or when small arms from the wounded are found in the hospital. Even if military forces misuse a hospital to store weapons or shelter able-bodied combatants, the attacking force must issue a warning to cease this misuse, setting a reasonable time limit for it to end, and attacking only after such a warning has gone unheeded.
Under the laws of war, doctors, nurses, and other medical personnel must be permitted to do their work and be protected in all circumstances. They lose their protection only if they commit, outside their humanitarian function, “acts harmful to the enemy.”
Likewise, ambulances and other medical transportation must be allowed to function and be protected in all circumstances. They could lose their protection only if they are being used to commit “acts harmful to the enemy,” such as transporting ammunition or healthy fighters in service. As stated above, the attacking force must issue a warning to cease this misuse, and can only attack after such a warning went unheeded.
Mosques and churches, like all houses of worship, and schools are presumptively civilian objects that may not be attacked unless they are being used for military purposes, such as a military headquarters or a location for storing weapons and ammunition.
The principle of proportionality also applies to these objects.
All sides were obligated to take special care in military operations to avoid damage to schools, houses of worship, and other cultural property.
As parties to the May 2021 armed conflict, the armed wings of Hamas, Islamic Jihad, and other Palestinian armed groups were obligated to abide by international humanitarian law. The targeting of military installations and other military objectives is permitted under the laws of war, but only if Hamas took all feasible precautions to avoid civilian harm. The laws prohibited Hamas from targeting civilians or launching indiscriminate attacks or attacks that would cause disproportionate harm to civilians compared to the expected military advantage. Hamas commanders were also obligated to choose such means of attack that they could direct at military targets and minimize incidental harm to civilians. If the weapons used were so inaccurate that they could not be directed at military targets without imposing a substantial risk of civilian harm, then it should not have deployed them.
The rockets launched by Palestinian armed groups – including locally made short and upgraded long-range rockets, “Grad” rockets, and rockets imported from other sources – are considered so inaccurate as to be incapable of being aimed in a manner to discriminate between military targets and civilian objects when they were launched toward populated areas. This inaccuracy and inability to target military objectives are exacerbated at the longer ranges that some rockets were fired into Israel.
The use of such rockets against civilian areas violates the prohibition on deliberate and indiscriminate attacks. Likewise, a party that launches rockets from densely populated areas, or co-locates military objectives in or near civilian areas – thus making civilians vulnerable to counterattacks – may be failing to take all feasible precautions to protect civilians under its control against the effects of attacks.
International humanitarian law allows the targeting of military commanders in the course of armed conflict, provided that such attacks otherwise comply with the laws that protect civilians. Political leaders not taking part in military operations, as civilians, would not be legitimate targets of attack.
Hamas leaders who were commanding belligerent forces would have been legitimate targets. However, because Hamas engages in civil governance beyond its military component, merely being a Hamas leader in and of itself does not make an individual lawfully subject to military attack.
Combatants do not have immunity from attacks in their homes and workplaces. However, as with any attack on an otherwise legitimate military target, the attacking force must refrain from attack if it would disproportionately harm the civilian population – including civilian family members of combatants – or be launched in a way that fails to discriminate between combatants and civilians. Under this duty to take all feasible precautions to avoid civilian harm, the attacking force should also consider whether there may be alternative sites where the combatant can be targeted without endangering civilians.
Attacking the home of a combatant who was not physically present at the time of the attack would in any event be an unlawful attack on a civilian object. If such an unlawful attack were carried out intentionally, then it would constitute a war crime. A civilian home does not lose its protected status as a civilian object merely because it is the home of a militant who is not present there. Insofar as the attack is designed to harm the combatants’ families, it would also be a prohibited form of collective punishment (see below).
The laws of war prohibit the punishment of any person for an offense other than one that they have personally committed. Collective punishment is a term used in international law to describe any form of punitive sanctions and harassment, not limited to judicial penalties, but including sanctions of “any sort, administrative, by police action or otherwise,” that are imposed on targeted groups of persons for actions that they themselves did not personally commit. The imposition of collective punishment – such as, in violation of the laws of war, the demolition of homes of families of fighters, or other civilian objects such as multi-story buildings as a form of punishment – is a war crime. Whether an attack or measure could amount to collective punishment depends on several factors, including the target of the measure and its punitive impact, but of particular relevance is the intent behind a particular measure. If the intention was to punish, purely or primarily as a result of an act committed by third parties, then the attack is likely to have been collective punishment.
Journalists and their equipment benefit from the general protection enjoyed by civilians and civilian objects and may not be targets of an attack unless they are taking direct part in hostilities. Journalists may be subject to legitimate limitations on rights, such as freedom of expression or freedom of movement, imposed in accordance with the law and only to the extent strictly required by the exigencies of the situation. But they may not be arrested, detained, or subjected to other forms of punishment or retaliation simply for doing their work as journalists.
Radio and television facilities are civilian objects and as such enjoy general protection. Military attacks on broadcast facilities used for military communications are legitimate under the laws of war, but such attacks on civilian television or radio stations are otherwise prohibited because they are protected civilian structures and not legitimate military targets. Moreover, if the attack is designed primarily to undermine civilian morale or to psychologically harass the civilian population, that is also a prohibited war purpose. Civilian television and radio stations are legitimate targets only if they meet the criteria for a legitimate military objective; that is, if they are used in a way that makes an “effective contribution to military action” and their destruction in the circumstances ruling at the time offers “a definite military advantage.” Specifically, Hamas-operated civilian broadcast facilities could have become military targets if, for example, they were used to send military orders or otherwise concretely to advance Hamas’s armed campaign against Israel. However, civilian broadcasting facilities are not rendered legitimate military targets simply because they spout pro-Hamas or anti-Israel propaganda – or report on the laws of war violations by one side or the other. Just as it is unlawful to attack the civilian population to lower its morale, it is unlawful to attack news outfits that merely shape civilian opinion by their reporting or create diplomatic pressure; neither directly contributes to military operations.
Should stations become legitimate military objectives because of their use to transmit military communications, the principle of proportionality in attack must still be respected. This means that Israeli forces should verify at all times that the risks to the civilian population in undertaking any such attack do not outweigh the anticipated definite military advantage. They should take special precautions in relation to buildings located in urban areas, including giving advance warning of an attack whenever possible.
Under international humanitarian law, parties to a conflict must allow and facilitate the rapid and unimpeded passage of impartially distributed humanitarian aid to the population in need. The belligerent parties must consent to allow relief operations to take place and may not refuse such consent on arbitrary grounds. They can take steps to ensure that consignments do not include weapons or other military materiel. However, deliberately impeding relief supplies is prohibited.
In addition, international humanitarian law requires that belligerent parties ensure the freedom of movement of humanitarian relief personnel essential to the exercise of their functions. This movement can be restricted only temporarily for reasons of imperative military necessity.
Serious violations of the laws of war that are committed with criminal intent are war crimes. War crimes, listed in the "grave breaches" provisions of the Geneva Conventions and as customary law in the International Criminal Court statute and other sources, include a wide array of offenses, including deliberate, indiscriminate, and disproportionate attacks harming civilians, using human shields, and imposing collective punishments, among others. Individuals also may be held criminally liable for attempting to commit a war crime, as well as assisting in, facilitating, aiding, or abetting a war crime.
Responsibility also may fall on persons planning or instigating the commission of a war crime. In addition, commanders and civilian leaders may be prosecuted for war crimes as a matter of command responsibility when they knew or should have known about the commission of war crimes and took insufficient measures to prevent them or punish those responsible.
States have an obligation to investigate and fairly prosecute individuals within their territory implicated in war crimes.
Alleged war crimes committed during the fighting between Israel and Hamas could be investigated by the International Criminal Court (ICC) prosecutor. On March 3, 2021, the ICC prosecutor opened an investigation into alleged serious crimes committed in Palestine since June 13, 2014. The ICC treaty officially went into effect for Palestine on April 1, 2015. The court’s judges have said this gives it jurisdiction over the territory occupied by Israel since 1967, namely Gaza and the West Bank, including East Jerusalem. The ICC has jurisdiction over war crimes and crimes against humanity committed in this territory, regardless of whether the perpetrator comes from a state that has joined the ICC.
Israel signed but has not ratified the ICC’s treaty, and in 2002 announced that it did not intend to become a member of the court.
Since 2016, Human Rights Watch has called on the ICC prosecutor to pursue a formal Palestine investigation given strong evidence that serious crimes have been committed there. The grave nature of many of the violations and the pervasive climate of impunity for those crimes make an ICC investigation necessary. The recent hostilities between Hamas and Israel highlight the importance of the court’s ongoing investigation of Israeli and Palestinian conduct. Human Rights Watch recently called on the ICC prosecutor also to investigate Israeli authorities implicated in the crimes against humanity of apartheid and persecution.
All governments should investigate and prosecute those credibly implicated in serious crimes, under the principle of universal jurisdiction and in accordance with national laws.
Member states at the Human Rights Council on May 27 voted to establish an ongoing Commission of Inquiry to address violations and abuses in the Occupied Palestinian Territory and in Israel, to monitor, document, and report on violations and abuses of international law, advance accountability for perpetrators and justice for victims, and address the root causes and systematic oppression that help fuel cycles of violence.
Drawing on years of research, Human Rights Watch found that Israeli officials have committed the crimes against humanity of apartheid and persecution.
The finding of apartheid is based on the intent of Israeli officials to maintain the dominance of Jewish Israelis over Palestinians across Israel and the Occupied Palestinian Territory, coupled with the systematic oppression of Palestinians and inhumane acts committed against them in the OPT, including East Jerusalem. These acts include sweeping restrictions on their movement; widespread land confiscation; the imposition of harsh conditions that have led thousands of Palestinians to leave their homes under conditions that amount to forcible transfer; the denial of residency rights to hundreds of thousands of Palestinians and their relatives; and the suspension of basic civil rights to millions of Palestinians. The finding of persecution is based on similar factors, including the discriminatory intent behind Israel’s treatment of Palestinians in Israel and the OPT and serious abuses in the OPT.
These findings do not change the legal status of the occupied territory, made up of the West Bank, including East Jerusalem, and Gaza, or the factual reality of occupation.
During armed hostilities over the last decade and more, Human Rights Watch has documented that the Israeli military and the armed wing of Hamas and other Palestinian groups have committed attacks on civilians and civilian objects in violation of the laws of war, which in many instances amounted to war crimes.