DEFINITIONS

International Humanitarian Law (IHL) and international criminal law distinguish between two principal categories of serious violations that constitute the most grave offenses against human dignity: war crimes and crimes against humanity. While both categories share certain elements and represent affronts to fundamental human rights, they operate under distinct legal frameworks with different thresholds, contextual requirements, and historical origins.

This analysis examines the legal definitions of these crimes as codified in the Rome Statute of the International Criminal Court (ICC) [1], the Geneva Conventions of 1949 [2], and the ICC's Elements of Crimes [3]. These documents will be referred to throughout the following sections.

The focus here remains strictly on legal definitions and elements, excluding enforcement mechanisms or prosecution strategies.

For comprehensive information visit the United Nations website.

Understanding the distinctions between war crimes and crimes against humanity is essential for accurate legal characterization and appropriate advocacy. While both categories address serious violations of human dignity and fundamental rights, they differ in critical respects.

*War crimes* require a significant connection to an armed conflict, either international or non-international in character. The contextual requirement is that the conduct took place "in the context of and was associated with" an armed conflict. No minimum scale or organizational pattern is required; even isolated violations occurring in the context of armed conflict may constitute war crimes [3].

*Crimes against humanity* require a widespread or systematic attack directed against a civilian population. Unlike war crimes, there is no requirement for an armed conflict nexus. The attack may occur during peace or war, so long as it meets the threshold of being widespread or systematic and is directed against civilians [1].

*War crimes* protect specific categories of persons and objects recognized under international humanitarian law: wounded and sick combatants, prisoners of war, civilians in occupied territories, medical personnel, humanitarian workers, and civilian objects such as schools, hospitals, and cultural property [2].

*Crimes against humanity* protect civilians without distinction, encompassing any civilian population subjected to attack. The protection is broader in scope but requires the contextual element of a widespread or systematic attack [1].

A fundamental distinction also lies in the policy requirement.

*Crimes against humanity* require that the attack be committed pursuant to or in furtherance of a State or organizational policy. This requirement reflects the gravity and systemic nature of these crimes, distinguishing them from isolated criminal acts [3].

*War crimes* do not require a policy element. Individual serious violations of IHL occurring in the context of armed conflict may constitute war crimes, regardless of whether they formed part of any plan or policy [3].

Both categories require intent and knowledge, but with a different focus [3]. 

For *war crimes*, the perpetrator must be aware of the factual circumstances establishing the protected status of persons or the character of the conflict.

For *crimes against humanity*, the perpetrator must know that their conduct was part of, or intended to be part of, a widespread or systematic attack against a civilian population.

*War crimes* have ancient roots in the laws of war, with formal codification beginning in the 19th century and accelerating after World War II through the Geneva Conventions and their Additional Protocols [2].

*Crimes against humanity* emerged as a distinct category following World War II, particularly through the Nuremberg Principles and subsequent international agreements.

Crimes against humanity represent one of the most serious categories of international crimes, addressing systematic or widespread attacks directed against any civilian population. The contemporary definition is primarily codified in Article 7 of the Rome Statute, which establishes both the contextual requirements (the "chapeau" elements) and the enumerated acts that constitute the crime [3].

Article 7(1) of the Rome Statute defines crimes against humanity as any of the following acts when committed as part of a widespread or systematic attack directed against any civilian population, with knowledge of the attack: murder, extermination, enslavement, deportation or forcible transfer of population, imprisonment, torture, rape, sexual slavery, enforced prostitution, forced pregnancy, enforced sterilization, sexual violence, persecution, enforced disappearance, apartheid, and other inhumane acts [1].

The contextual requirements for crimes against humanity (commonly referred to as the "chapeau" elements) establish the threshold that distinguishes isolated criminal acts from systemic human rights violations qualifying as crimes against humanity. These elements serve as gatekeepers, ensuring that only the most serious and systematic violations fall within this category.

*First*, the attack must be either widespread or systematic. The Rome Statute employs the disjunctive "or," meaning that either element alone may satisfy this threshold. "Widespread" refers to the large-scale nature of the attack, reflecting the number of victims and the geographic scope of the acts. "Systematic" refers to the organized nature of the attack, suggesting a pattern or plan rather than random acts. The Elements of Crimes clarifies that this requirement reflects the need for conduct that is impermissible under generally applicable international law [3].

*Second*, the attack must be directed against a civilian population. This element requires that the civilian population be the primary object of the attack, rather than military objectives or combatants. The attack may involve the multiple commission of acts referred to in Article 7(1) against any civilian population, pursuant to or in furtherance of a State or organizational policy to commit such an attack [3].

*Third*, the perpetrator must have knowledge that their conduct was part of, or intended to be part of, a widespread or systematic attack against a civilian population. Importantly, this mental element does not require knowledge of all characteristics of the attack or the precise details of the State or organizational policy. In cases of emerging widespread or systematic attacks, the intent element is satisfied if the perpetrator intended to further such an attack [3].

Each enumerated act under Article 7(1) carries distinct elements that must be proven independently. The Elements of Crimes provides detailed specifications for each crime, though certain commonalities exist across the category.

*Murder* requires that the perpetrator killed one or more persons, with the killing constituting part of a widespread or systematic attack against civilians and the perpetrator having knowledge of this [3].

*Extermination* involves killing, including by inflicting conditions of life calculated to bring about the destruction of part of a population, constituting or taking place as part of a mass killing of members of a civilian population [3].

*Enslavement* requires the perpetrator to exercise any or all of the powers attaching to the right of ownership over one or more persons, such as through purchasing, selling, lending, or bartering persons, or imposing similar deprivations of liberty. The definition explicitly includes trafficking in persons, particularly women and children [3].

*Deportation or forcible transfer of population* involves the deportation or forcible transfer of persons to another State or location without grounds permitted under international law, where such persons were lawfully present in the area from which they were transferred [3].

*Imprisonment or severe deprivation of physical liberty* requires imprisonment or severe deprivation of liberty of such gravity that it violates fundamental rules of international law, with the perpetrator aware of the factual circumstances establishing this gravity [3].

*Torture* requires the infliction of severe physical or mental pain or suffering upon persons in the custody or under the control of the perpetrator, with the pain or suffering not arising solely from lawful sanctions [3].

*Sexual crimes* under Article 7(1)(g) include rape, sexual slavery, enforced prostitution, forced pregnancy, enforced sterilization, and sexual violence. Each carries specific elements, with rape requiring invasion of the body by penetration through force, threat of force, or coercion, or against a person incapable of giving genuine consent [3].

*Persecution* requires severe deprivation of fundamental rights contrary to international law, targeting persons by reason of the identity of a group or collectivity, based on political, racial, national, ethnic, cultural, religious, gender, or other universally recognized impermissible grounds, committed in connection with any Article 7(1) crime or any crime within the Court's jurisdiction [3].

*Enforced disappearance* involves the arrest, detention, or abduction of persons followed by a refusal to acknowledge such deprivation of freedom or give information on the fate or whereabouts of such persons, carried out by or with the authorization of a State or political organization, with intent to remove such persons from the protection of the law for a prolonged period [3].

*Apartheid* requires the commission of inhumane acts in the context of an institutionalized regime of systematic oppression and domination by one racial group over another, with intent to maintain the regime [3].

*Other inhumane acts* encompasses acts of a character similar to any other Article 7(1) acts, causing great suffering or serious injury to body, mental, or physical health [3].

War crimes (also known as violations of the laws and customs of war) concern serious breaches of international humanitarian law applicable in armed conflict. The legal framework for war crimes derives from multiple sources: the Geneva Conventions of 1949 and their Additional Protocols, customary international law, and the Rome Statute's Article 8 [2].

The Geneva Conventions establish the foundational protections for persons protected during armed conflict, while Article 8 of the Rome Statute provides a comprehensive enumeration of war crimes within the ICC's jurisdiction [1].

The four Geneva Conventions each contain a common Article 3 addressing non-international armed conflicts, as well as provisions addressing international armed conflicts [2]: 

• Geneva Convention for the Amelioration of the Condition of the Wounded and Sick in Armed Forces in the Field (Convention I) 
• Geneva Convention for the Amelioration of the Condition of Wounded, Sick and Shipwrecked Members of Armed Forces at Sea (Convention II) 
• Geneva Convention Relative to the Treatment of Prisoners of War (Convention III)
• Geneva Convention Relative to the Protection of Civilian Persons in Time of War (Convention IV)

These and other humanitarian treaties and documents can be read in full on the International Humanitarian Law (IHL) Treaties Database. The International Committee of the Red Cross (ICRC) is a Geneva-based, neutral, and independent humanitarian organization.

Particular significance attaches to "grave breaches" as defined in the Geneva Conventions. Under the Conventions, grave breaches constitute the most serious violations committed against protected persons or property, giving rise to universal jurisdiction obligations on States parties to search for and prosecute alleged perpetrators [2].

Common Article 146 (Convention I), Article 147 (Convention III), Article 147 (Convention IV), and analogous provisions establish that grave breaches include: willful killing, torture, or inhumane treatment including biological experiments, willfully causing great suffering or serious injury to body or health, unlawful deportation or transfer, unlawful confinement, and taking hostages [2].

Article 8 of the Rome Statute enumerates war crimes in comprehensive detail, distinguishing between international and non-international armed conflicts and between different categories of protected persons and objects [1].

*Article 8(2)(a)* addresses war crimes committed in international armed conflicts against persons protected under the Geneva Conventions, including: willful killing, torture, inhuman treatment, biological experiments, willfully causing great suffering, destruction and appropriation of property not justified by military necessity, compelling service in hostile forces, denying fair trial, unlawful deportation or transfer, unlawful confinement, and taking hostages [3].

*Article 8(2)(b)* addresses serious violations of the laws and customs of applicable in international armed conflict, including: attacking civilians or civilian objects, attacking humanitarian personnel or peacekeeping missions, launching indiscriminate attacks causing excessive incidental harm, attacking undefended places, killing or wounding persons hors de combat, improper use of flags of truce or emblems, transferring civilian population into occupied territory, attacking protected objects, mutilation or medical experiments, treacherous killing, denying quarter, destroying enemy property, pillage, employing poison or prohibited weapons, and sexual violence [3].

*Article 8(2)(c)* addresses serious violations of Common Article 3 applicable to non-international armed conflicts, including: murder, mutilation, cruel treatment, torture, outrages upon personal dignity, taking hostages, and sentencing or execution without due process [3].

*Article 8(2)(e)* addresses other serious violations of the laws and customs applicable in armed conflicts not of an international character, mirroring many of the Article 8(2)(b) prohibitions [3].

The Elements of Crimes document specifies the mental and material elements required for each war crime. For most war crimes under Article 8, there is no requirement for a legal evaluation by the perpetrator as to the existence of an armed conflict or its character as international or non-international. Similarly, there is no requirement for awareness by the perpetrator of the facts establishing the character of the conflict. Rather, there is only a requirement for awareness of the factual circumstances establishing the existence of an armed conflict, which is implicit in the requirement that the conduct "took place in the context of and was associated with" an armed conflict [3].

For example, the war crime of willful killing under Article 8(2)(a)(i) requires: (1) the perpetrator killed one or more persons; (2) such persons were protected under one or more Geneva Conventions; (3) the perpetrator was aware of the factual circumstances establishing protected status; (4) the conduct took place in the context of and was associated with an international armed conflict; and (5) the perpetrator was aware of factual circumstances establishing the existence of an armed conflict [3].

Universal jurisdiction represents a principle of international law permitting any State to prosecute individuals for certain grave crimes regardless of where the crime was committed or the nationality of the perpetrator or victim. This principle operates as an exception to the traditional territorial and nationality bases for criminal jurisdiction.

The foundation for universal jurisdiction in international criminal law derives from the grave breaches provisions of the Geneva Conventions. Under Common Article 146 of the Geneva Conventions, States parties undertake to enact legislation necessary to provide effective penal sanctions for persons committing or ordering grave breaches, and to search for such persons and bring them before their own courts or hand them over for trial to another State concerned [2].

The Rome Statute's preamble and Article 12(2) establish the ICC's jurisdiction based on the territorial or national principle (the State on whose territory or of whose nationals the crime occurred), but the Statute does not itself establish universal jurisdiction for national courts, leaving that determination to domestic law [1].

Customary international law recognizes universal jurisdiction for piracy, slavery, war crimes, crimes against humanity, and genocide. For war crimes, universal jurisdiction is firmly established through the Geneva Conventions' express provisions. For crimes against humanity, universal jurisdiction has gained recognition particularly where the crimes were committed as part of a systematic or widespread practice [2].

You may download the following English language PDFs directly from this site.

The ICRC Geneva Conventions of 12 August 1949

UN Geneva Convention on Civilian Protection

ICC Rome-Statute

The UN Rome Statute of The International Criminal Court

ICC Elements Of Crimes

International Instruments For The Prevention And Sanction Of Torture

For more downloads, including those written in languages other than English, visit the United Nations Hub for International Law, the International Criminal Court Resource Library, and Law and Policy at the International Comittee for The Red Cross.

. . .

PREVIOUS · HOME | NEXT · REPORTING