About this topic
International Humanitarian Law (IHL) is the body of international law that governs how armed conflict is fought. It answers practical questions that arise on the battlefield. The three problems below are solved at the end of these notes with the exact rule that applies.
Problem 1 (the pilot): A fighter aircraft is hit by a missile. The pilot ejects and drifts down by parachute directly above a line of enemy soldiers. One soldier takes aim with a rifle. May the soldier fire?
Problem 2 (the illegal war): One state launches a completely unjustified attack on its neighbour. The neighbour defends itself and captures 500 attacking soldiers. Its commander declares that since these soldiers came to fight an illegal war, the Geneva rules do not protect them. Is the commander right?
Problem 3 (the ambulance): An ambulance painted with a red crescent is stopped at a checkpoint. Inside, along with one injured patient, soldiers find boxes of ammunition meant for fighters at the front. Is the ambulance still protected?
Jus ad bellum and jus in bello
The boxing match: Two separate questions can be asked about a boxing match. First, should the match have taken place at all, and was it properly licensed? Second, once the bell rings, how must the boxers fight (no blows below the belt, no punching a boxer who is down)? Even if the match was wrongly organised, the rules inside the ring still bind both boxers. International law asks the same two questions about war.
Jus ad bellum (law on going to war)
Jus ad bellum is a Latin phrase meaning the law on going to war. It governs whether a state may use force at all.
Its foundation today is Article 2(4) of the United Nations Charter, 1945:
"All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations."
There are two main exceptions to this prohibition:
- Self-defence against an armed attack under Article 51 of the UN Charter.
- Force authorised by the Security Council under Chapter VII of the UN Charter.
Jus in bello (law in war)
Jus in bello means the law in war. It governs how the fighting must be conducted. This is International Humanitarian Law, also called the law of armed conflict.
- It protects people who are not fighting, or who have stopped fighting.
- It restricts the weapons and tactics that may be used.
- It does not decide who was right to start the war. It only governs behaviour once the fighting has begun.
| Point | Jus ad bellum | Jus in bello (IHL) |
|---|---|---|
| Meaning | Law on going to war | Law in war; law of armed conflict |
| Question answered | May a state use force at all? | How must the fighting be conducted? |
| Boxing analogy | Should the match take place; was it licensed? | Rules inside the ring once the bell rings |
| Main source | Article 2(4) UN Charter, 1945; exceptions in Article 51 and Chapter VII | Geneva Conventions, Additional Protocols, Hague law |
Separation of the two and equality of belligerents
As in the boxing match, the two bodies of law are kept apart. The preamble of the First Additional Protocol of 1977 reaffirms that the Geneva Conventions and the Protocol:
"must be fully applied in all circumstances to all persons who are protected by those instruments, without any adverse distinction based on the nature or origin of the armed conflict or on the causes espoused by or attributed to the Parties to the conflict".
This is the principle of equality of belligerents.
Why equality of belligerents is necessary: almost every state claims that its own war is just. If protection under IHL depended on who was right to go to war, each side would deny protection to the other. So IHL binds both sides equally, whatever the lawfulness of the war.
Two streams of IHL: Geneva law and Hague law
Humanitarian law grew out of the experience of two men, in two different wars, in the middle of the nineteenth century. Each started a separate stream of rules.
| Point | Geneva law | Hague law |
|---|---|---|
| Focus | The person in front of the weapon | The weapon in the soldier's hand |
| What it does | Protects those outside the fighting: the wounded, the sick, the shipwrecked, prisoners of war and civilians | Regulates the means and methods of warfare |
| Founder | Henry Dunant (Battle of Solferino, 1859) | Francis Lieber (American Civil War; Lieber Code, 1863) |
Henry Dunant and the Geneva stream
The Battle of Solferino (1859)
Henry Dunant was a businessman from Geneva in Switzerland. His company in Algeria needed permission to use water, which only the French Emperor, Napoleon III, could grant. Dunant set off to meet him even though the Emperor was leading an army in northern Italy.
On 24 June 1859, Dunant reached the area around Solferino just as one of the bloodiest battles of that century was ending. The armies of France and Sardinia had fought the Austrian army, and tens of thousands of soldiers lay killed or wounded with almost no one to treat them.
Dunant set aside his business and helped organise local people, especially the women of nearby Castiglione, to wash wounds, give water and comfort the dying, whatever uniform they wore. The women summed up their attitude in two Italian words, tutti fratelli, meaning "all are brothers".
A Memory of Solferino (1862) and its results
In 1862, Dunant published a small book, A Memory of Solferino. It proposed two things:
- Relief societies in every country, with volunteers trained in peacetime to help the wounded in war.
- A treaty protecting wounded soldiers and those who care for them.
Both ideas came true quickly:
- 1863: a committee of five Geneva citizens, Dunant among them, was formed. It later became the International Committee of the Red Cross (ICRC).
- 1864: states adopted the first Geneva Convention, for the wounded in armies in the field.
- 1901: Dunant shared the first Nobel Peace Prize.
The ICRC is still based in Geneva and works as a neutral, impartial humanitarian body in conflicts worldwide.
Development of the Geneva Conventions
- 1864: the first Geneva Convention, the seed of the Geneva stream.
- 1906: the Convention was revised.
- 1929: revised again, and a separate Convention on prisoners of war was also adopted.
- Second World War: exposed huge gaps, above all for civilians.
- 12 August 1949: states adopted the four Geneva Conventions that form the core of IHL today.
The four Geneva Conventions of 1949
To remember them, follow a soldier's journey: wounded on land, wounded at sea, captured, and finally the civilians around him.
| Convention | Whom it protects |
|---|---|
| First Geneva Convention | Soldiers wounded or sick on land |
| Second Geneva Convention | Those wounded, sick or shipwrecked at sea |
| Third Geneva Convention | Soldiers who are captured: prisoners of war |
| Fourth Geneva Convention | Civilians, especially those in enemy hands and in occupied territory (entirely new; it steps outside the army) |
Key rules of the Third Convention (prisoners of war)
Article 13 (humane treatment):
"Prisoners of war must at all times be humanely treated."
Prisoners of war must be protected against violence, intimidation, insults and public curiosity. So parading them before cameras to humiliate them is not allowed.
Article 17 (limited disclosure):
"Every prisoner of war, when questioned on the subject, is bound to give only his surname, first names and rank, date of birth, and army, regimental, personal or serial number, or failing this, equivalent information."
No torture or coercion may be used to extract more.
Article 118 (release and repatriation):
"Prisoners of war shall be released and repatriated without delay after the cessation of active hostilities."
Captivity is not punishment. It only keeps a soldier out of the fight until the fighting ends.
Key rules of the Fourth Convention (civilians)
- Article 34 (hostages): "The taking of hostages is prohibited."
- Article 33 (collective punishment): no one may be punished for an offence he or she has not personally committed. It adds: "Collective penalties and likewise all measures of intimidation or of terrorism are prohibited."
- Article 28 (human shields): "The presence of a protected person may not be used to render certain points or areas immune from military operations."
India and the Geneva Conventions
Every state in the world has accepted the Geneva Conventions. India ratified them in 1950 and gave effect to them through the Geneva Conventions Act, 1960.
Section 3(1):
"If any person within or without India commits or attempts to commit, or abets or procures the commission by any other person of, a grave breach of any of the Conventions he shall be punished, where the offence involves the wilful killing of a person protected by any of the Conventions, with death or with imprisonment for life; and in any other case, with imprisonment for a term which may extend to fourteen years."
Section 3(2):
"Sub-section one applies to persons regardless of their nationality or citizenship."
| Grave breach under Section 3(1) | Punishment |
|---|---|
| Involving wilful killing of a person protected by any of the Conventions | Death or imprisonment for life |
| Any other case | Imprisonment up to 14 years |
Section 3 covers committing, attempting, abetting or procuring a grave breach, by any person, within or without India, and regardless of nationality or citizenship. So a grave breach is punishable in India wherever it happens and whoever commits it.
The Additional Protocols
Three Additional Protocols later supplemented the Geneva Conventions.
| Protocol | Adopted | Scope |
|---|---|---|
| First Additional Protocol | 8 June 1977 | International armed conflicts, including (under Article 1(4)) armed conflicts in which peoples fight against colonial domination, alien occupation and racist regimes in the exercise of their right of self-determination; strengthened civilian protection and put the basic targeting principles into treaty form |
| Second Additional Protocol | 8 June 1977 | Certain non-international armed conflicts, inside a single state |
| Third Additional Protocol | 8 December 2005 | Emblems; created the red crystal |
Article 1(4) of the First Additional Protocol extends it to:
"armed conflicts in which peoples are fighting against colonial domination and alien occupation and against racist régimes in the exercise of their right of self-determination".
India is not a party to the First and Second Additional Protocols, though many of their rules are now regarded as customary international law.
The Third Additional Protocol and the red crystal
The red cross and the red crescent tell everyone that a hospital, an ambulance or a medical worker must not be attacked. But in some conflicts, the cross or the crescent was seen as a religious or national symbol, which weakened its protective force. So the Third Protocol created an emblem without such meaning, popularly called the red crystal.
Article 2 describes it as "composed of a red frame in the shape of a square on edge on a white ground", and declares: "The distinctive emblems shall enjoy equal status."
Francis Lieber and the Lieber Code
Francis Lieber was a German-born scholar settled in the United States. As a young man he had been wounded as a soldier in the Napoleonic wars, and the American Civil War split his own family, with sons on opposite sides.
At the request of the Union's military leadership, he drafted a code of conduct for the army. President Abraham Lincoln issued it on 24 April 1863 as General Orders No. 100, known as the Lieber Code.
Article 16 of the Lieber Code captures the spirit of IHL:
"Military necessity does not admit of cruelty, that is, the infliction of suffering for the sake of suffering or for revenge, nor of maiming or wounding except in fight, nor of torture to extort confessions."
Legal status of the Lieber Code: it was national law, an order to one country's army, and not a treaty between states. Its importance lies in its influence: it proved that the laws of war could be written down in detail, and it inspired later international texts, especially the Hague Regulations.
The Hague stream: Peace Conferences of 1899 and 1907
In 1899, on the initiative of the Russian Tsar, Nicholas II, states met at The Hague in the Netherlands for an International Peace Conference. A second conference followed in 1907. The Tsar's main aim was to slow the arms race.
The scorecard of the Hague Conferences
1. Limitation of armaments: this was the very reason for calling the 1899 conference. Yet states could not agree, and nothing binding was adopted at either conference.
The next three items are Declarations of 1899.
2. Declaration on balloons: aeroplanes did not yet exist (the Wright brothers flew only in 1903), so balloons were then the main way of rising into the sky.
"The Contracting Powers agree to prohibit, for a term of five years, the launching of projectiles and explosives from balloons, or by other new methods of a similar nature."
Because the ban was only for five years, the 1907 conference renewed it.
3. Declaration on poison gas:
"The Contracting Powers agree to abstain from the use of projectiles the object of which is the diffusion of asphyxiating or deleterious gases."
Asphyxiating means causing suffocation; deleterious means harmful.
4. Declaration on expanding bullets:
"The Contracting Parties agree to abstain from the use of bullets which expand or flatten easily in the human body, such as bullets with a hard envelope which does not entirely cover the core, or is pierced with incisions."
Such bullets open up inside the body and cause terrible wounds. They were popularly called Dum Dum bullets, after the British arsenal at Dum Dum, near Kolkata, where they were developed.
The gas and bullet Declarations had no time limit, so they simply continued, and the 1907 conference adopted nothing new on them.
| Item | 1899 | 1907 | Result |
|---|---|---|---|
| Limitation of armaments | No agreement | No agreement | Failed twice |
| Projectiles from balloons | Banned for 5 years | Ban renewed | Banned, then renewed |
| Asphyxiating or deleterious gases | Banned (no time limit) | Nothing new | Banned since 1899 |
| Expanding (Dum Dum) bullets | Banned (no time limit) | Nothing new | Banned since 1899 |
The Hague Convention and Hague Regulations on land warfare
The conferences also adopted a Convention on the laws and customs of war on land, revised in 1907 as the Fourth Hague Convention. Its annexed Hague Regulations contain perhaps the central sentence of Hague law, in Article 22:
"The right of belligerents to adopt means of injuring the enemy is not unlimited."
Article 23 then lists specific prohibitions, beginning with poison or poisoned weapons, and including arms calculated to cause unnecessary suffering.
The Martens Clause
The 1899 conference also produced the Martens Clause, named after Fyodor Martens, the Russian jurist and diplomat who proposed it. The delegates knew that written rules could never cover every situation, so they placed a safety net in the preamble.
Its modern version is Article 1(2) of the First Additional Protocol:
"In cases not covered by this Protocol or by other international agreements, civilians and combatants remain under the protection and authority of the principles of international law derived from established custom, from the principles of humanity and from the dictates of public conscience."
New autonomous weapons controlled by software are not specifically mentioned in any treaty. A state cannot claim that it may use them however it likes. The Martens Clause fills that silence with the principles of humanity and the dictates of public conscience.
The two streams merge
The two streams did not stay apart. The Additional Protocols of 1977 contain rules of both kinds, so the line between Hague law and Geneva law now mainly explains how the law developed.
When does IHL apply? The three-position switch
The application of IHL can be pictured as a switch with three positions.
| Switch position | Situation | Rules that apply |
|---|---|---|
| Fully on | International armed conflict | Full IHL; Common Article 2 of the Geneva Conventions |
| On, with a smaller set of rules | Non-international armed conflict inside one state | Common Article 3; the Second Additional Protocol if its higher threshold is met |
| Off | Internal disturbances and tensions | Domestic law and human rights law, not IHL |
Position 1: International armed conflict (switch fully on)
Article 2, common to all four Geneva Conventions:
"In addition to the provisions which shall be implemented in peacetime, the present Convention shall apply to all cases of declared war or of any other armed conflict which may arise between two or more of the High Contracting Parties, even if the state of war is not recognized by one of them. The Convention shall also apply to all cases of partial or total occupation of the territory of a High Contracting Party, even if the said occupation meets with no armed resistance."
Under Common Article 2, no formal declaration of war is needed, and occupation is covered even without a shot fired.
Position 2: Non-international armed conflict (switch on, smaller set of rules)
A non-international armed conflict takes place inside one state, between government forces and organised armed groups, or between such groups. Article 3, common to all four Geneva Conventions, applies. It provides that:
"Persons taking no active part in the hostilities, including members of armed forces who have laid down their arms and those placed hors de combat by sickness, wounds, detention, or any other cause, shall in all circumstances be treated humanely, without any adverse distinction founded on race, colour, religion or faith, sex, birth or wealth, or any other similar criteria."
It then prohibits, "at any time and in any place whatsoever", four things:
- "violence to life and person, in particular murder of all kinds, mutilation, cruel treatment and torture";
- "taking of hostages";
- "outrages upon personal dignity, in particular humiliating and degrading treatment"; and
- "the passing of sentences and the carrying out of executions without previous judgment pronounced by a regularly constituted court, affording all the judicial guarantees which are recognized as indispensable by civilized peoples."
Common Article 3 is called a "convention in miniature" because it packs the essence of the Geneva Conventions into one article.
How serious must internal violence be?
Tadic case (1995), International Criminal Tribunal for the former Yugoslavia: the Tribunal gave the leading answer on when an armed conflict exists. Held: "an armed conflict exists whenever there is a resort to armed force between States or protracted armed violence between governmental authorities and organized armed groups or between such groups within a State." Principle: for internal violence, two things matter: the intensity of the fighting and the organisation of the armed group.
The Second Additional Protocol sets a higher bar for itself. It requires an armed group:
- under responsible command;
- controlling part of the territory well enough to carry out sustained and concerted military operations; and
- able to apply the Protocol.
Position 3: Internal disturbances and tensions (switch off)
Article 1(2) of the Second Additional Protocol:
"This Protocol shall not apply to situations of internal disturbances and tensions, such as riots, isolated and sporadic acts of violence and other acts of a similar nature, as not being armed conflicts."
Such situations are governed by domestic law and human rights law, not IHL.
Three days of violent street protests, with stones thrown and tear gas fired, are serious, but they are not an armed conflict; the switch is off. By contrast, a rebel army with a clear command, uniforms and heavy weapons, holding a mountain region for two years and fighting regular battles with the national army, is a different matter; there the switch is on.
The four pillars of IHL
When the switch is on, everything rests on four pillars, each tested by one question.
| Pillar | Test question |
|---|---|
| Distinction | Who or what may be targeted? |
| Military necessity | Is this force really needed to defeat the enemy? |
| Proportionality | Will the expected civilian harm be excessive? |
| Humanity | Does this cause suffering that serves no military purpose? |
1. Distinction
Article 48 of the First Additional Protocol:
"In order to ensure respect for and protection of the civilian population and civilian objects, the Parties to the conflict shall at all times distinguish between the civilian population and combatants and between civilian objects and military objectives and accordingly shall direct their operations only against military objectives."
An army fuel depot beside a primary school is a military objective. The school is not.
Civilians are protected, in the words of Article 51(3), "unless and for such time as they take a direct part in hostilities."
A shopkeeper who fires at soldiers can be targeted while doing so.
Protection of persons hors de combat
Linked to distinction is the protection of those out of the fight, called hors de combat (a French expression). Article 41 provides:
"A person who is recognized or who, in the circumstances, should be recognized to be hors de combat shall not be made the object of attack."
This covers:
- a person in enemy hands;
- a person clearly offering to surrender; and
- a person unconscious or too wounded or sick to defend themselves,
provided they commit no hostile act and do not try to escape.
Article 42(1) adds:
"No person parachuting from an aircraft in distress shall be made the object of attack during his descent."
2. Military necessity
Military necessity allows what is genuinely required to weaken the enemy's military forces.
Military necessity is a reason, not a licence. It never justifies what the law forbids, as Article 16 of the Lieber Code already made clear.
3. Proportionality
Under Article 51 of the First Additional Protocol, an attack is indiscriminate, and so prohibited, if it is:
"an attack which may be expected to cause incidental loss of civilian life, injury to civilians, damage to civilian objects, or a combination thereof, which would be excessive in relation to the concrete and direct military advantage anticipated."
A bridge is the only supply route for enemy tanks, so it is a military objective. Bombing it at 9 in the morning, when it is crowded with buses of office workers, may cause clearly excessive civilian deaths. Destroying it at 3 in the morning, when it is almost empty, may well be lawful.
- Commanders must also take all feasible precautions in choosing means and methods of attack.
- Proportionality is judged on what could reasonably be expected when the decision was made, not with hindsight.
4. Humanity
Article 35 of the First Additional Protocol provides:
"In any armed conflict, the right of the Parties to the conflict to choose methods or means of warfare is not unlimited."
It continues:
"It is prohibited to employ weapons, projectiles and material and methods of warfare of a nature to cause superfluous injury or unnecessary suffering."
Applications of this principle:
- A Protocol of 1995 bans laser weapons designed to cause permanent blindness.
- A Protocol of 1980 bans weapons that injure by fragments invisible to X-rays, which no surgeon could find.
Humanity also guards survival and heritage:
- Article 54: "Starvation of civilians as a method of warfare is prohibited."
- The Hague Convention of 1954 protects cultural property, such as historic monuments, archaeological sites and museums.
- Article 53 forbids acts of hostility against historic monuments, works of art or places of worship that form the cultural or spiritual heritage of peoples.
IHL and human rights law
If human rights law already protects life and dignity, IHL is still needed because the two do different jobs.
Think of a large building. Human rights law is its structure, standing every day in every weather. IHL is the fire-safety plan, switched on only when fire breaks out. During the fire, the structure still stands, but the plan tells everyone exactly how to act.
| Point | Human rights law | IHL |
|---|---|---|
| When it applies | At all times, in peace and in armed conflict | Only in armed conflict |
| Whom it binds | Mainly places duties on the state | Binds every party, including organised armed groups |
| Suspension in emergency | Some rights may be temporarily restricted in a public emergency | Cannot be suspended on the ground of emergency, because its rules were written for the greatest emergency of all |
| Modern foundation | Universal Declaration of Human Rights, adopted by the UN General Assembly on 10 December 1948 | Geneva Conventions, Additional Protocols and Hague law |
When both apply, IHL acts as the special law.
Legality of the Threat or Use of Nuclear Weapons (1996), Advisory Opinion of the International Court of Justice: the ICJ considered how human rights law and IHL relate in armed conflict. Held: the right not to be arbitrarily deprived of life continues in war, but whether a killing in hostilities is arbitrary must be judged by IHL. Principle: in armed conflict, IHL operates as the special law within which human rights are interpreted.
Enforcement of IHL
- Serious violations of IHL are war crimes, and the individuals who commit them can be punished, as India's Geneva Conventions Act, 1960 shows.
- Internationally, the Rome Statute of 1998 created the International Criminal Court (ICC). Its Article 8 lists war crimes.
- India is not a party to the Rome Statute.
Solving the three problems
Problem 1: the descending pilot
- The soldier must not fire. Article 42 of the First Additional Protocol forbids attacking a person parachuting from an aircraft in distress during the descent, and the rule is widely accepted as customary law.
- After landing in enemy territory, the pilot must be given a chance to surrender, unless the pilot is clearly engaging in a hostile act.
- Airborne troops dropped in for an attack are not covered by this protection.
Problem 2: soldiers of an illegal war
- The commander is wrong. Whether the war was lawful is a jus ad bellum question.
- Inside the ring, jus in bello binds both sides equally (equality of belligerents).
- The captured soldiers are prisoners of war, fully protected by the Third Geneva Convention.
Problem 3: the ambulance carrying ammunition
The ambulance may lose protection, but not automatically. Article 21 of the First Geneva Convention, which Article 35 of that Convention extends to medical transport, provides:
"The protection to which fixed establishments and mobile medical units of the Medical Service are entitled shall not cease unless they are used to commit, outside their humanitarian duties, acts harmful to the enemy. Protection may, however, cease only after a due warning has been given, naming, in all appropriate cases, a reasonable time limit, and after such warning has remained unheeded."
- Protection is lost only if the unit is used, outside its humanitarian duties, to commit acts harmful to the enemy.
- Even then, protection ceases only after a due warning, naming a reasonable time limit in appropriate cases, has remained unheeded.
- The injured patient inside stays protected throughout.
- Misusing the emblem is itself prohibited, because it destroys the trust that keeps every genuine ambulance safe.
Quick revision
- Two questions: jus ad bellum (whether a state may use force; Article 2(4) UN Charter, exceptions in Article 51 and Chapter VII) and jus in bello (how the fighting is conducted; IHL). They are kept apart: equality of belligerents.
- Two founders and two streams: Henry Dunant (Solferino, 1859) with Geneva law, which protects the person; Francis Lieber (Lieber Code, 1863) with Hague law, which regulates the weapon.
- A switch with three positions: international armed conflict (Common Article 2), non-international armed conflict (Common Article 3; Tadic test; Second Additional Protocol threshold), and internal disturbances (switch off).
- Four pillars: distinction, military necessity, proportionality and humanity.
