Public International Law

Public International Law (PIL) rests upon two core concepts enmeshed in each of its underlying regimes: those of sovereignty and non-intervention. These privileges are allotted only to recognized States as qualified by the standards set forth in the Montevideo Convention of 1933. Article 1 of the Convention articulates that “the state as a person of international law should possess the following: a) a permanent population; b) a defined territory; c) government; and d) capacity to enter into relations with other states”.1 Non-intervention of States into the affairs of other States is a far-reaching principle with only two exceptions: Security Council authorization under Chapter 7 of the UN Charter, and self-defense. Sovereignty is a more detailed principle as States strip away particular aspects of their sovereignty with each treaty and agreement signed. Beyond governing States, PIL also regulates international organizations and the relationships among these organizations, States, and individuals.

The sources of PIL are international conventions, international custom, the general principles of law recognized by civilized nations, and judicial decisions and the teachings of the most highly qualified publicists of the various nations.2 While States may decide which conventions to ratify, international customary law applies to all State regardless of consent. To qualify as international custom, a law must be a consistent and general practice among States and must be adhered to by those States out of a sense of legal obligation rather than political action or diplomacy.

The legal regimes within PIL which most relate to humanitarian action are International Humanitarian Law (IHL), International Human Rights Law (HRL), and Refugee Law.

International Humanitarian Law

Although IHL as a legal concept has existed for centuries, contemporary IHL was first codified in 1863/4 with the Lieber Code and the first Geneva Convention for the Amelioration of the Condition of Wounded in Armies in the Field. These legal codes established on both sides of the Atlantic differed widely despite their chronological symmetry. The Lieber Code presented Rules of Engagement emphasizing military necessity for the American Civil War, whereas the first Geneva Convention established the ICRC, emphasizing humanity in light of Henry Dunant’s A Memory of Solferino. The 1949 Geneva Conventions and their Additional Protocols bring together four key principles: military necessity, humanity, distinction, and proportionality. Together with the 1907 Hague Convention on the means and methods of warfare, the four Geneva Conventions and their three Protocols supply the treaty-based framework for IHL. Much of the content of the Geneva Conventions is now considered customary law; however, there is debate among States over which rules apply. The ICRC created a database on what they consider to be customary IHL, however this source is non-binding and functions as guidance only.

IHL regulates the relationship between parties engaged in armed conflict. To date, the Geneva Conventions have 194 states party, and the additional protocols I and II have 170 and 165 states party, respectively. Where there are non-State actors (NSA), and therefore non-signatories, engaged in the conflict, customary IHL governs their actions. NSAs may adopt the conventions voluntarily for a number of reasons, including fostering legitimacy of the group in the international arena.

The First Geneva Convention regulates treatment of the sick and wounded in the field. The Second concerns the sick and wounded in air and at sea. The Third regulates the treatment of prisoners of war. The Fourth concerns the protection of civilians in wartime. Additional Protocol I regulates international armed conflicts, while Additional Protocol II regulates non-international armed conflicts. IHL faces a challenge as only Additional Protocol II and Common Article 3 of the four Geneva Conventions regulate non-international armed conflict. There are over 500 laws governing conduct in international armed conflict; however, there are only around 26 to govern those intra-state conflicts which account for the majority of armed conflicts today.

Human Rights Law

While IHL governs only in times of conflict, International Human Rights Law (HRL) governs in times of peace. Yet there is some overlap between the two regimes during conflict as the central core of HRL, the non-derogable, preemptory jus cogens norms apply at all times. These norms are customary law and include: the right to be free from the arbitrary depravation of life; the right to be free from slavery; the right to be free from torture, cruel, or inhuman treatment; and the principle of non-refoulement. Beyond customary HRL, there are multiple treaty-based laws in effect at both the international and the regional level.

Although the notion of human rights was broadcast during the 18th century revolutions in the United States and France, HRL is a younger legal regime than IHL in that its codification was a product of the 20th century post-war world. Focusing on the relationship of States and individuals within their jurisdiction, HRL was implied in the UN Charter but explicitly detailed in the Universal Declaration of Human Rights (UDHR). The UDHR is considered to be reflective of customary law. This document, along with the International Covenant on Civil and Political Rights (ICCPR) and the International Covenant on Economic, Social and Cultural Rights (ICESCR), makes up what is commonly referred to as the International Bill of Rights. In total, there are nine core human rights treaties at the international level. They are, listed in descending order by number of states party: Convention on the Rights of the Child (CRC, 193 parties); Convention on the Elimination of All Forms of Discrimination Against Women (CEDAW, 187 parties); International Convention on the Elimination of All Forms of Racial Discrimination (ICERD, 175 parties); ICCPR (167 parties); ICESCR (160 parties); Convention Against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment (CAT, 150 parties); the Convention on the Rights of Persons with Disabilities (CRPD, 112 parties); International Convention on the Protection of the Rights of All Migrant Workers and Members of Their Families (ICRMW, 45 parties); and the International Convention for the Protection of All Persons from Enforced Disappearance (CPED, 32 parties).

In addition to international treaties, there are several regional human rights treaties and courts: the European Convention on Human Rights; the American Convention on Human Rights; the African Charter on Human and Peoples Rights; the Arab Charter on Human Rights; and the Asian Human Rights Charter. The most established of these regional systems is the European system, begun in 1950. The regionalization of HRL is a distinct characteristic of this legal regime, not seen in IHL or Refugee Law.

Refugee Law

Refugee Law aims to protect individuals fleeing armed conflict and/or human rights violations by crossing international borders. This regime exists in conjunction with IHL and HRL, allowing refugees all the protections normally allotted in times of conflict or peace. A refugee is defined by Article 1 of the 1951 Convention Relating to the Status of Refugees as someone who, “owing to wellfounded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group or political opinion, is outside the country of his nationality and is unable or, owing to such fear, is unwilling to avail himself of the protection of that country; or who, not having a nationality and being outside the country of his former habitual residence as a result of such events, is unable or, owing to such fear, is unwilling to return to it.”3 It is important to note that a person fleeing persecution and remaining within the borders of their country of origin is not a refugee, therefore not eligible for the protections granted under Refugee Law. These individuals are internally-displaced persons (IDPs) and subject to standards set forth under UN Guiding Principles, IHL, HRL, and domestic law. The core principle of Refugee Law, non-refoulement, spans across HRL and Refugee Law as a preemptory norm, ineligible for any derogations. Beyond this key customary rule, Refugee Law is codified in the 1951 Convention Relating to the Status of Refugees and its 1967 Protocol.

Together with International Criminal Law, these three legal regimes form the basis of international law applicable in times of armed conflict. Although the Geneva Conventions contain the most provisions regarding humanitarian action and assistance, both HRL and Refugee Law establish protections for vulnerable populations as well. The Convention Relating to the Status of Refugees requires State parties to cooperate with the UN High Commissioner for Refugees in the operation of its functions. Within HRL, beyond the jus cogens norms, the ICCPR and CRC both provide for food, medical treatment, and shelter. A knowledge of the requirements and foundations of these legal regimes and of PIL in general are essential to ensuring effective humanitarian action.


1Montevideo Convention, Article 1, 1933
2Statute of the ICJ, Article 38, 1945
3Convention Relating to the Status of Refugees, Article 1, 1951.

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