All about International law

The study of international law, also known as public international law or the law of nations, is the body of legal rules, norms, and standards that apply between sovereign states and other entities that are legally recognized as global actors. The term was coined by the English philosopher Jeremy Bentham (1748–1832).

International law’s structure and development

Definition and scope of application

International law is defined by Jeremy Bentham as a collection of regulations concerning state-to-state interactions, according to the standard definition. It reflects how far international law has progressed that the original description omits people and international organizations—two of the most active and important aspects of contemporary international legal systems.

International law, furthermore, no longer should be regarded as a set of rules; rather, it is a rapidly developing complex of rules and influential–though not directly enforceable—principles, practices, and assertions linked with increasingly sophisticated structures and procedures. International law, in its most basic sense, provides norms as well as methodologies and a common theoretical language to international actors — that is, primarily sovereign nations but also increasingly global organizations and some individuals.

International law has evolved into a much broader field, with issues ranging from human rights to economic and trade matters, space law, and international organizations now included. Although international law is not a moral system but rather a legal one, it has been influenced by ethical ideas and concerns, especially in the area of human rights.

International law is not the same as international comity, which refers to courteous non-binding customs adopted by governments for reasons of etiquette (for example, saluting foreign navy vessels at sea).

International law is a term used to describe the study of international legal issues, and it differs from conflict of laws (private international law), which focuses on the national legal systems of different nations where foreign elements exist.

International law is a system of law that exists outside of the legal systems of individual countries. It differs from national legal systems in a variety of ways. Although the United Nations (UN) General Assembly, which includes representatives from almost every country on Earth, appears to be a legislative body, it has no authority to make binding laws.

The UN may only implement recommendations in specific circumstances and for certain purposes within the UN system, such as establishing the UN budget, admitting new members of the United Nations, and, with Security Council involvement, selecting new judges to the International Court of Justice (ICJ). There is also no such thing as an international law court system.

The court’s jurisdiction in contentious cases is based on the consent of the involved states. There is no international police force or comprehensive system of law enforcement, and there is no supreme executive authority. The UN Security Council may authorize the use of force to induce countries to follow its decisions only in certain and limited cases; essentially, there must be a preceding act of aggression or the threat thereof.

Finally, any such legal action may be vetoed by any of the council’s five permanent members (China, France, Russia, the United Kingdom, and the United States), making the decision-making process rather time-consuming. Because there is no standing UN military, individual nations must band their forces together on an ad hoc basis.

The study of international law is a specialized topic that brings into play many fields of study. Because states frequently consider relevant international laws when considering responses to a particular international issue, it’s important to understand the fundamental structure of multilateral relations.

Nonetheless, states are usually cautious to ensure that their activities adhere to the rules and principles of international law since doing so would be regarded unfavorably by the international community. International law is typically not enforced through the use of military force or even economic sanctions. Rather, reciprocity or a sense of enlightened self-interest sustain the system.

A country’s violation of international norms erodes its legitimacy, which can have a detrimental impact on future diplomatic ties with other nations. As a result, one state breaching an agreement to its advantage may induce other states to violate additional treaties and therefore cause damage to the initial offender. Furthermore, it is generally acknowledged that repeated rule breaches would jeopardize the system’s value to the international community of states and international organizations. The value of international norms derives from the fact that there are rules accepted by all international actors. International law also establishes a framework for global interaction as well as a shared set of concepts for comprehending it.

Historical growth

The long-standing principle of international law is that independent sovereign states are the only relevant actors in the international system. During the European Renaissance, however, the fundamental structure of international law was determined.

The earliest known treaties were a treaty between the rulers of Lagash and Umma (in Mesopotamia) from about 2200 BCE, as well as an agreement between Egyptian pharaoh Ramses II and Hattusilis III, the king of the Hittites, signed in 1258 BCE. After that, numerous Middle Eastern empires entered into several pacts.

The long and rich cultural histories of ancient Israel, India, and China contributed to the formation of international law. Furthermore, ancient Greek political philosophy and the interactions between Greek city-states provided crucial sources for the development of the international legal system.

The Roman Empire established many of the principles that now underpin the global legal system. The Romans developed the jus gentium (law of nations) to regulate the position of aliens and their interactions with Roman citizens. According to Greek natural law, which they accepted, the Romans conceived of the jus gentium as having worldwide application.

Natural law, infused with religious ideas from the writings of Moses Maimonides (1135–1204), was developed in the Middle Ages, and the theologian St. Thomas Aquinas (1224/25–1274), who became the intellectual basis of the new field of international law, which is defined as that branch of natural law that applied to sovereign state interactions.

For nearly 500 years, Europe was torn by numerous conflicts following the fall of the western Roman Empire in the 5th century CE.Eventually, a pack of nation-states formed, and a number of supranational rules were developed to govern interstate interactions, including canon law, the legal system (which governed trade), and various maritime codes—e.g., the Laws of Bishop Grosseteste (c. 1175), The Code of Hammurabi, the 7th-century Hittite and Assyrian laws, and the 12th-century Rolls of Oléron (named for an island off the west coast of France) are just a few examples.

The introduction of the printing press in the 15th century and the arrival of Greek scholars from the crumbling Byzantine Empire sparked scientific, humanistic, and individualist thought development in Europe. The expansion of European explorers’ ocean navigation throughout the world introduced European norms across the globe and expanded western Europe’s intellectual and geographical horizons.

The growth in trade, the consolidation of European nations with growing wealth and ambitions, and the establishment of a framework of rules to regulate their interactions all contributed to the need for a system. The concept of sovereignty, which had previously been used to argue for the entrenchment of power in the person of the king, was later transformed into a principle of collective sovereignty as the divine right of kings gave way legally to parliamentary or representative forms of government in the 16th century. The phrase “sovereignty” acquired two additional meanings in the twentieth century, one of which was with respect to international politics. It referred to independence within a system of competing nation-states.

The Italian lawyers Bartolo da Sassoferrato (1313/14–1357) and Baldo degli Ubaldi (1327–1400), both regarded as the originator of modern private international law study, wrote on these topics.

The modern theory, however, can be traced to the Spanish Golden Age philosophers of the 16th and 17th centuries. Francisco de Vitoria (1486–1546) and Francisco Suárez (1548–1617) both emphasized that international law was founded on natural law. In 1598 Italian jurist Alberico Gentili (1552–1608), considered the founder of the secular school of international law, published De jure belli libri tres (1598; Three Books on the Law of War), the Natural Law, which was used to defend the rights of individuals and communities in a monarchy, became an umbrella term that labeled any political theory that rested on naturalistic rather than theological assumptions. The law of nature changed from a theological notion to a secular philosophy based on reason with Gentili’s work.

Hugo Grotius, a Dutch jurist known as the “father of international law,” has had a significant impact on the field, particularly in regard to his 1625 work De Jure Belli ac Pacis ( On the Law of War and Peace). His reputation as the father of international law, however, may have been exaggerated. Grotius organized international law into a complete system, notably in De Jure Belli ac Pacis (1625; On the Law of War and Peace), excising it from political theology. The freedom of the high seas, which Grotius emphasized, became quickly popular among northern European nations engaged in major missions of exploration and settlement all around the world.

Hugo Grotius

Naturalists and positivists can be identified among Grotius’s followers. Samuel von Pufendorf, a German jurist and natural philosopher, was one of the early Enlightenment thinkers whose works influenced John Locke. In contrast, Richard Zouche (1590–1661) in England and Cornelis van Bynkershoek (1673–1743) in the Netherlands stressed actual state practice over theories derived from biblical sources, Greek thought, or Roman law.

These latest writings also placed a greater emphasis on the law of peace and interstate conduct than they did on the law of war, as the primary focus of international law shifted away from the criteria needed to invoke force in response to increasingly sophisticated interstate relations such as maritime and trade pacts.

The positivist approach to philosophy made use of the contemporary scientific method and was, in that respect, comparable to the empiricist and inductive way of thinking that was becoming popular in Europe at the time. Both positivism and natural law may be found in the works of German philosopher Christian Wolff (1679–1754) and Swiss jurist Emerich de Vattel (1714–67), both of whom attempted to create a middle way between the schools.

During the 18th century, the naturalist school was gradually eclipsed by the positivist approach, yet at the same time, natural rights, which featured a significant role in the American and French revolutions, were gaining prominence in global politics. Natural rights, on the other hand, had little significance in international law until the 20th century.

Positivism, which can be traced back to the Enlightenment and was most popular during the imperialistic and industrial Victorian century, when the notion of state sovereignty was bolstered by exclusive domestic jurisdiction and nonintervention in other states’ affairs—ideas that had been disseminated throughout the globe by Europe’s colonial powers.

In the 20th century, positivism’s dominance in international law was shattered by two world wars, which resulted in the formation of numerous global organizations—such as the League of Nations and UN—as well as an increase in importance of human rights.

After becoming geographically global through the European colonial expansion, international law became genuinely worldwide during the first decades following World War II, when decolonization resulted in the formation of a number of new sovereign states.

The inclusion of a new group of nations, the state’s diverse political and economic goals and needs, as well as their varied cultural traditions, infused the previously European-dominated principles and techniques of international law with new influences.

International political events shape the development of international law—both its rules and institutions—over time. The Cold War, which pitted the Soviet Union and its allies against the United States and its allies, dominated much of this period.

Because resolutions proposed by one side were likely to be vetoed by the other, the UN Security Council was unable to function as intended. The bipolar system of alliances contributed to the formation of regional organizations.—e.g., The Soviet Union, on the other hand, sought to extend its reach through proxy wars and invasions throughout Asia and Africa. The United States was wary of this strategy, which is called “containment,” since it led to conflict on the peripheries of both blocs—as witnessed in Korea, Vietnam, and Berlin.

Finally, norms for the protection of human rights developed unevenly, hampered by deep political differences.

The Cold War also saw the emergence of a group of nonaligned and frequently newly decolonized countries known as the “Third World,” whose support was eagerly sought by both the United States and the Soviet Union. The growing importance of the developing world drew the attention of countries, particularly regarding decolonization, racial prejudice, and economic assistance.

This change in international relations was accompanied by major advancements in international politics and law. The ICJ’s charter, for example, mandated that the court’s organization be influenced by the world’s most prevalent civilizations and legal systems.

The conference also decided to maintain and develop an agreement under the United Nations that establishes equitable regional representation in the UN Security Council through nonpermanent seats. The five permanent seats on the Security Council have regularly gone to Africa or Asia, two to Latin America, and one each to Europe and other countries. Other UN bodies are organized similarly.

Tensions increased between states of the north and those of the south, especially on issues such as trade, human rights, and the law of the sea, as a result of the collapse of the Soviet Union and end of the Cold War in the early 1990s.

With the dramatic rise in international trade, services, currency, information, and people—all thanks to technological development and globalization—Globalization became an important factor, spurring global cooperation and somewhat reducing ideological barriers that separated the world. Despite this, globalization has also promoted trade conflicts between friends like the United States and the European Union (EU).

Globalization has produced a proliferation of international and regional organizations in the last three decades, and it has necessitated the development of international law to cover the rights and duties of these actors.

New international law is frequently produced via methods requiring near-unanimous agreement as a result of its complexity and the many actors its impacts. For example, multilateral talks have been used in place of bilateral negotiations to transform the process of state consent into community acceptance in such areas as the environment.

In the process of consensus-building, various environmental agreements and the Law of the Sea treaty (1982) have been reached. International law is a complicated system. However, in practice, while the concept of sovereign equality is “vertical,” owing to states’ disproportionate importance in creating and maintaining international law, some countries remain more significant than others.

International and municipal law are two different things

In general, international law functions only at the global level and not within national legal systems, which is by positivism’s view that international law and local law are separate and autonomous systems.

The major argument against it is that natural laws, on the other hand, cannot be proved neither in practice nor by deduction. This type of legal theory is referred to as monism because it maintains a single legal system made up of both municipal and international law. monists believe that a system like this could emerge from either a unified ethical approach emphasizing worldwide human rights or a formalistic, hierarchical approach claiming the existence of one fundamental norm supporting both international law and local legislation.

The principle that no local rule may be used as a defense for violating international law has been recognized in both international case law (such as the Alabama claims case between the United States and the United Kingdom following the American Civil War) and treaties (Article 27 of the 1969 Vienna Convention on the Law of Treaties).

The position of international law within municipal legislation is more nuanced, and it depends on a country’s domestic laws. Treaties must be distinguished from customary international law in particular.

Treaties are legal documents that must be signed and ratified by the parties, which means they are legally enforceable. The rules of customary international law are those norms established as a result of state behavior.

The Constitution of the United States states (Article VI, Section 2) that “treaties shall be the supreme Law of the Land.” The president negotiates treaties but they must be ratified by two-thirds of the Senate except in special circumstances (Article II).

A treaty may be either self-executing or non-self-executing, depending on whether domestic legislation is required for the treaty to take effect. A self-executing agreement in the United States takes immediate effect and need not be followed. The courts’ view matters when determining whether a convention is self-executing.

In Sei Fujii v. State of California (1952), the state’s high court determined that the UN Charter was not self-executing since its fundamental principles regarding human rights lacked the necessary mandatory quality and certainty to generate judiciable rights for private persons; since then, other courts in the United States have applied it.

The Paquette Habana case (1900) demonstrates the distinction. The United States Supreme Court ruled that international law prohibits the United States Navy from selling, as prizes of war, Cuban fishing boats it had seized, in this instance. Even if a domestic law goes against international law, it is supreme in the United States.

As a result of this concern, it is assumed that the U.S. Congress will not pass legislation contrary to the nation’s international agreements.

The United Kingdom is an incorporation country, believing that customary international law is a component of common law. British law, on the other hand, considers treaties to be purely executive rather than legislative acts.

Thus, only if relevant legislation is passed will a treaty become part of domestic law. The same principle holds true in other countries where the English common law has been incorporated (e.g., the majority of Commonwealth states and Israel). Although customary law is considered part of the law of the land in the incorporation view, municipal rules take precedence over international law in cases of conflict.

The incorporation of foreign law into municipal legislation is a contentious issue in common-law countries that have adopted a formal constitution.In addition, the articles of a treaty concluded in accordance with a country’s constitution may be applied only to public funds and not to private ones. Cyprus’ treaties have a higher status than local law on the condition of reciprocity, according to its constitution.

The adoption of a treaty is a legislative act in most civil-law nations. The status of an international treaty within national law varies by country, and its constitutional provisions control the relationship between municipal and international law. International law is complicated to apply in federal systems, and international legal norms are usually considered to be a part of federal legislation.

Although a treaty generally only becomes effective when it has been ratified by a national parliament, EU countries have decided that regulations and judgments issued by EU bodies are directly applicable and enforceable without the need for enabling legislation—except for the fact that the country’s entry into the union has granted permission for this sort of legislation making, which is subsequently implemented after the country joins the union (e.g., Britain’s adoption of the European Communities Act in 1972).

The most important sources of international law are the following:

The International Court of Justice (ICJ) derives its power from Article 38 (1) of the ICJ’s statute, which refers to three sources of international law: treaties, custom, and general principles. Because the worldwide legal framework is both horizontal and decentralized, the formulation of international laws is inherently more intricate than local laws.

Treaties

Treaties are referred to by a number of names, including conventions, agreements, pacts, general acts, charters, and covenants. The participants in such written agreements (usually but not always states) agree to be bound by the negotiated terms. The prior question refers to agreements that are governed by municipal law, in which case international law is irrelevant. The category of treaties does not include informal, nonbinding political statements or declarations.

Treaties can be either bilateral or multilateral. Treaties with numerous parties are more likely to have international significance, although many of the most important treaties (e.g., those resulting from Strategic Arms Limitation Talks) have been bilateral. Contemporary treaties such as the Geneva Conventions (1949) and the Law of the Sea treaty (1982; formally, the United Nations Convention on the Law of the Sea), with more than 150 parties, demonstrate both their significance and how far international law has evolved into a tool for broad legislation. The Genocide Convention (1948), the Vienna Convention on Diplomatic Relations (1961), the Antarctic Treaty (1959), and the Rome Statute establishing the International Criminal Court are just a few of the more significant treaties. Some treaties, for example, create international organizations and lay out their constitutions (e.g., UN Charter of 1945) (e.g., visa regulations, travel arrangements, and bilateral economic assistance).

Non-signatories are not bound by the treaty’s provisions. Nonetheless, treaty provisions might under some circumstances serve as the basis of an international custom, especially if they can be generalized or are “of a fundamentally norm-creating nature,” as the ICJ called the North Sea Continental Shelf (1969) procedures.

A treaty is made up of the parties’ consent, is enforceable, and must be carried out in good faith. The Latin phrase pacta sunt servanda (“agreements must be kept”) may arguably be considered the foundation of international law. No international agreement would be binding or effective without it.

The Latin phrase pacta sunt servanda is frequently used in international agreements governing treaties, including the Vienna Convention on Treaties between States (1969) and the Vienna Convention on Treaties Between States and International Organizations or International Organizations (1986).

There is no formal treaty-making procedure. Heads of state or government departments may draft them. The state’s consent for the conclusion of a treaty is the most crucial aspect, which may be signaled by signature, instrument exchange, ratification, or accession. Ratification is the most common form of consent—unless the contract is a minor one, in which case a signature is usually enough. Depending on the country’s constitutional structure, ratifying techniques differ.

Treaties may allow signatories to opt out of a specific provision, allowing nations that accept the basic principles of a treaty to become parties even though they might have concerns about peripheral issues. These worries are referred to as “reservations,” which are different from interpretative declarations and have no legal force.

Reservations to a treaty are permissible where the treaty does not prohibit them and as long as they are compatible with the treaty’s goal and purpose. Reservation of rights is permitted in some countries, which means that reservations are accepted or refused by other nations. In the former case, the treaty as modified by the terms of the reservations enters into force between the parties concerned.

In the case of a post-conflict settlement, the treaty comes into effect between the concerned parties except for those sections to which reservations have been made and to the extent of those reservations. The main drawback of this method is that each government has the authority to determine whether reservations are acceptable, and there can be a disagreement about the legal implications if a reservation is ruled unlawful.

A set of rules to interpret treaties has emerged. Given the context, object, and goal of a treaty, it is expected that it be interpreted in good faith and by normal meanings of its words. When the term of the agreement is open, supplementary methods of interpretation such as the employment of travaux préparatoires (French: “preparatory works”) and a look at the circumstances surrounding the treaty’s conclusion may be utilized.

A more flexible approach to treaty interpretation, based on the principle of effectiveness (i.e., an interpretation that would not allow the provision in question to become ineffective) combined with a broader-purpose approach (i.e., paying attention to the fundamental objectives of the treaty while interpreting a particular provision), has been employed in some situations.

A more programmatic or purpose-oriented approach is used in order to aid an international organization in coping with change when the treaty is also its constitutional document.

For what has been characterized as “living instruments,” such as human rights treaties that establish an implementation system, a purpose-oriented approach has also been suggested; In the case of the European Convention on Human Rights of 1950, this perspective has enabled the criminalization of homosexuality to be considered a violation of human rights in recent years even though it was common practice when the document itself was signed.

The termination or interruption of a treaty may be initiated by one of its provisions (if any exist) or by the agreement of the signatories. If neither is the case, other sections might come into play. If a treaty is terminated or suspended owing to a material breach by one of the parties, the innocent party has the right to do so.

The termination of multilateral treaties is more difficult. All the parties may cancel or suspend the treaty in its entirety or in part, and a particularly affected party can temporarily suspend it with the defaulting state.

The parties may suspend the entire agreement or a portion of it if any substantial violation of the contract would substantially alter each party’s obligations under the treaty.

The International Court of Justice, for example, issued an advisory opinion in 1971 that regarded the General Assembly’s decision to terminate the mandate for southwest Africa as lawful. A breach of a treaty is considered important if there has been an unconstitutional disavowal of the treaty or a violation of an essential provision to the treaty’s purpose or objective.

A party may withdraw from or terminate a treaty if there has been a fundamental change of circumstances, as stipulated by the term rebus sic stantibus (Latin: “things standing thus”).

An obvious example is a sunken island that has become relevant. However, merely a substantial change in circumstances is not enough to warrant termination or withdrawal unless the original conditions were an essential basis of the parties’ agreement to be bound by the treaty, and the shift transforms the degree of obligations yet to be fulfilled.

In such cases, however, the exception does not apply if the treaty establishes a boundary or if the fundamental change is caused by a party’s breach of an obligation under the treaty or any other international duty owed to another party.

Custom

The ICJ’s statute refers to “international custom, as evidence of a general practice accepted as law,” as a second source of international law. Custom, which reflects the decentralized nature of the international system, comprises two key elements: the actual practice of states and the acceptance by states of that practice as law.

Several elements of a state’s materiality (also known as the “materiality” of a state) include the length, consistency, repetition, and breadth of certain types of actions by states.

At the end of the day, whether a particular practice becomes an enforceable international custom is judged by how well each element fits into this construct. The International Court of Justice has stated that customs must be “continuous and uniform” usage or “widely and nearly uniformly” used in order to be considered enforceable. Although all states may contribute to the formation of a new or modified custom, they are not all treated equally throughout the procedure.

The primary states have a more significant role in the creation of customs. For example, during the 1960s, while the United States and the Soviet Union had far more influence on space law than did the countries that had little or no previous experience with it.

The second element converts a merely utilized habit into a legal custom—the practice must be accepted as opinio juris sive necessitatis (Latin: “opinion that an action is required by law”).

In the North Sea Continental Shelf cases, the ICJ ruled that practice must have “taken place in such a manner as to demonstrate a general awareness that a rule of law or legal obligation was involved.”

A custom is binding on all states in the international community, even if individual states have not consented unless a state has objected from the start of the custom—a stringent test to show.

The right to create a custom depends on the state in which the practice is conducted. Some requirements apply only to a certain group of states (e.g., Latin American nations), while others are limited to two states, and the required standard for recognition as a custom is often high.

A generalizable treaty provision, a binding customary rule, and a multilateral treaty provision on the same subject matter (e.g., the right to self-defense) may all exist at the same time.

General principles of law

The ICJ’s statute also identifies a third source of international law: “the generally accepted principles of law recognized by civilized nations.” These concepts, in essence, provide a means for addressing international problems that are not covered by existing treaty rules or authoritative binding customary norms.

The basic ideas behind any given legal system are general principles that may be derived through either municipal or international law. Many of them, on the other hand, is evidential or procedural principles, as well as those concerned with the judicial process’s machinery – e.g., the principle established in Chorzow Factory (1927–28), which Accordingly, in the Chorzow Factory case, Poland was obliged to pay compensation to Germany for the illegal expropriation of a factory.

The value of good faith may be the most fundamental tenet of international law. It regulates the formation and performance of legal duties, as well as treaty law’s foundation.

Another key general principle is equity, which allows for flexibility in the application and enforcement of international law. For example, the Law of the Sea Convention stipulated that states with opposing or adjacent coasts should negotiate their coastal boundaries on a basis of equity.

Other potential resources

The International Court of Justice’s statute, Article 38 (1), also allows judicial rulings and academic writings as supplemental methods for determining the law. Judicial decisions from both local and foreign authorities may help to create new norms and regulations. International legal rules may be made evident through their consistent application by several states’ courts in municipal cases.

However, the best method of legal determination is established by the international judicial decisions of organizations such as the ICJ in The Hague, UN International Tribunal for the Law of the Sea at Hamburg (Germany), and international arbitral tribunals.

Other factors may lay the groundwork for worldwide law. UN General Assembly Resolutions are not enforceable in all cases, except organizational procedure in certain circumstances—but they can be extremely influential. Resolutions may help to create new customary rules, both in terms of state practice and through the process of establishing a custom, by demonstrating the adoption by countries of the notion “as law” (opinio juris).

A resolution must have a big idea and appeal to a wide range of countries with various ideological, cultural, and political viewpoints in order to succeed. The following are a few examples of such declarations: the Declaration on the Granting of Independence to Colonial Nations and Peoples (1960), the Declaration on Legal Principles Governing Activities of States in the Exploration and Use Of Outer Space (1963), and the Declaration on International Law Concerning Friendly Relations and Co-operation Among States (1970).

A state’s unilateral actions might create legal responsibilities if it is clear that the government intends to be bound by the obligation and when its intention is openly declared. France’s decision to cease atmospheric nuclear testing during litigation at the ICJ with Australia and New Zealand (1974) regarding the legality of such testing is an example of this type of situation.

Unilateral claims might provide insight into a country’s concerns on a certain topic. Even when an instrument or document does not create a legal obligation, it may weigh on the international community.

The Helsinki Accords (1975), which sought to reduce tensions between the Soviet Union and the United States during the Cold War, were not legally enforceable, but they had significant political consequences. A variety of recommendations, standards, guidelines, codes of conduct, and other suggestions may generate what is known as “soft law” in certain areas—that is, an instrument that has no legal worth but establishes a significant statement.

Source and norm hierarchies

The general principles of customary international law are compatible with treaty law. Sources that are more recent in origin are typically assigned greater authority, and specific rules take precedence over general ones. Jus cogens (Latin: “compelling law”) norms are imperious rules that states cannot deviate from; they have a higher ranking than jus dispositivum (Latin: “law subject to the parties’ discretion”), or normal intergovernmental rules, and can be altered only by subsequent norms of equal or higher rank.

The rules in the first category include those against genocide, slavery, and piracy, as well as the outlawing of violence. Other examples of jus cogens laws are more contentious. A treaty will be invalid if, at the time it is concluded, it contradicts a peremptory norm of general international law. (Article 53) The Vienna Convention on the Law of Treaties states that a treaty will be void if it conflicts with a peremptory norm of general international law at the time of its conclusion.

A peremptory norm of general international law is a legal rule that, without any further qualification, unequivocally precludes the wrongdoing of the State. In order for a jus cogens norm to be formed, the fundamental must first be recognized as a rule of international law by the international community and then adopted as such.

Furthermore, international law has established a category of erga omnes (Latin: “towards all”) duties that apply to all countries. In standard obligations, the defaulting state is responsible to specific interested states (for example, other parties to the treaty that has been broken), but in the case of erga omnes obligations, all states have an interest and may take measures in reaction.