International law

Table of Contents

International law, that is, the order of the international community, reveals its structural characteristics through the principles relating to subjects, sources, ways of settling disputes, and means of ensuring compliance with the rules.

International law relates to the policies and procedures that govern relationships among nations (Clarkson, Miller, & Cross, 2018). These are crucial for businesses for multiple reasons. First, there is not a single authoritative legislative source for global business affairs, nor a single world court responsible for interpreting international law (Cheeseman, 2016, p. 903). There is also not a global executive branch that enforces international law, which leaves global business affairs particularly vulnerable.

Secondly, if a nation violates international law and persuasive tactics fail, then the countries that were violated, or international organizations tasked with overseeing global trade, may act. Often these actions use force to correct the offenses and may include economic sanctions, severance of diplomatic relations, boycotts, or even war against the offending nation (Clarkson, Miller, & Cross, 2018, p. 439).

The purpose of international laws is to permit countries as much authority as possible over their own international business affairs while maximizing the economic benefits of trade and working relationships with other nations. Since many countries have historically allowed governance by international agreements when conducting global business, there exists an evolving body of international laws that facilitate global trade and commerce.

The main difference between the structure of international law and that of domestic law is the absence of a central authority that issues the law and ensures its respect (this is the so-called “anarchy” of the international community), moreover, since the end of the 19th century and especially since the end of the First World War, States have been joined by International Organizations, while with the beginning of decolonization, insurrectional movements have progressively assumed international legal personality, provided they exercise effective control over a population and a territory.

Within a state system, the recognition of legal personality in favor of collective bodies and organizations implies that these new subjects are subject to a special discipline, that is different from the common one intended to protect and promote the interests of individuals. In the international legal system, on the contrary, the discipline of common law concerns bodies and organizations, in particular States. While domestic law determines the requirements that bodies and organizations must meet in order to obtain recognition of legal personality, international law does not prescribe how a state must be constituted, but rather ascertains its existence.

Some experts believe that recent developments in the field are slowly leading to the emergence of an international legal subjectivity of individuals, a position opposed by most scholars, who believe that the international scene is still dominated by States and supranational organizations, despite the increasingly important role played by individuals and NGOs. Recognition of the international personality of individuals rests on the growing number of international rights and obligations that accrue to individuals as such and not as citizens of a state, such as human rights and individual international responsibility (international crimes).

In fact, international law is sometimes scholastically divided into public international law and private international law; according to this scholastic division, public international law deals with the relations between sovereign states and between them and organizations of international law; private international law, on the other hand, deals with the relations between a state and private foreign citizens or relations between citizens and foreign states or international organizations. This heading deals with what is called public international law. The essence of international law is its being international, therefore with jurisdiction over a plurality of states or in places not regulated by national laws, for example the sea and the cosmos. Private international law is often understood as the discussion of economic and commercial matters that may fall under international commercial law, regulated by special international treaties and by the relevant bodies of the United Nations and supranational bodies such as the European Commission and the European Parliament.

To make a clear distinction between private and public law in the international field is rather complicated because it is mainly concerned with the discussion of issues that require the examination of a set of rules more or less attributable to national law but generally referred to the complex of rules and international treaties governing relations between States, issues relating to supranational organizations, disputes ‘extraterritorial’ and relations between companies acting in the international arena, or in more nations. The subdivision between public international law and private international law is however contested by numerous scholars. Private international law, notwithstanding its appellation of international, is in fact the set of rules of domestic law (i.e., proper to a state system, and promulgated in the manner provided for by the system of the state itself) that resolve conflicts between the provisions of different legal systems applicable to the same relationship, when there are links to more than one national legislation. Therefore, for private international law, the appropriate internal rules apply. The result is that the two typologies refer to completely different branches of the legal system, the so-called public one to the system of the Community of States (or international), while the private one to the internal system of each State.

For the above reasons, the term public for International Law in the proper sense is also criticized, since the definition of public can only refer to a state order.


Its origin is historically linked to the formation of sovereign and independent States, which, following the Peace of Westphalia (1648), gave rise to the first nucleus of today’s international community. Given the equal structure of this community, international law is characterized by the fact that the functions of production, ascertainment and coercive implementation of the rules are carried out, in the absence of organs superordinate to the States, by the subjects themselves, according to the model of functional decentralization.

The end of the Second World War saw with the Nuremberg Trial for the first time individuals who had held high governmental positions being called to answer personally for crimes committed in the name of their State against other peoples before an international tribunal, while traditionally international responsibility is collective (directed against the State as a whole). The Statute of the International Criminal Court, recently entered into force (but not ratified by many states, including the United States) includes in the notion of international crime genocide, crimes against humanity (the definition includes virtually any serious crime committed on a large scale and systematically and the practice of apartheid), war crimes under International Humanitarian Law and war of aggression.

Some international treaties stipulated after World War II, such as the European Court of Human Rights, provide for the possibility of individuals to apply independently to international bodies to have their rights respected, without the mediation of States. Recent developments in international law, particularly in the field of the protection of human rights, have led some scholars to believe that an international juridical subjectivity of individuals is slowly emerging, breaking with the dictates of classical international law.

Customary law and conventional (or covenant) law

Given the absence of a universal legislature capable of valid and binding legislation, universally valid international law is mostly customary law, although the policies of international organizations such as the UN can influence its development (e.g. on the use of force in international relations). In order to become part of customary law, a rule must be accepted by at least a large majority of states, including the most influential international states.

Conventional law, on the other hand, is based on international agreements freely entered into by states, which undertake to abide by their provisions. As a rule, treaty law prevails over customary law (i.e. particular law prevails over general law), but with a very important exception regarding jus cogens. A norm of ius cogens is a customary norm that protects values considered fundamental and which cannot be derogated from in any way: if two States stipulate a treaty in which they propose to carry out violations of the integrity of a third State or to execute actions considered international crimes, the treaty itself is considered null and void.

Forms, contents and procedures for the formation of the conventional law have been codified in the Vienna Convention on the Law of Treaties; in the Preamble of this Convention it is specified that the rules of customary international law will continue to regulate the matters not regulated by the provisions of the Convention itself, also because the Convention represents only a point of reference and does not necessarily coincide with the international customs on the subject.


The following entities are subjects of international law:

  • States that meet the requirements of effectiveness and independence (meaning the State in its meaning of State-Organization, i.e., the set of rulers and government apparatuses);
  • International Organizations, including in particular the UN, its Auxiliary Bodies and related organizations.
  • The Holy See (not to be confused with the Vatican City State).
  • Movements that substantially exercise control over a territory and a population, while not having formal control, such as the Insurgents. While as far as liberation movements are concerned, these are not given a real legal personality, but rather the right to take part in international meetings dealing with the self-determination of peoples.

The subjectivity of some entities is, however, under discussion. They are generally not considered subjects of international law:

  • The peoples themselves, although having recognized the right of self-determination, are not considered subjects of international law. In fact, they lack the characteristics of a stable organization and the presence of governmental institutions.
  • Non-governmental organizations are not considered subjects of international law even if many treaties attribute them an international role (e.g. the Red Cross).
  • Part of the doctrine recognizes a limited international subjectivity also to individuals by referring to the growing body of norms relating to the international law of human rights, i.e. those norms of international law that protect the human dignity of the individual, especially in relation to the State (not to be confused with international humanitarian law which, being part of the international law of war, comes into force during armed conflicts regulating the conduct of the belligerents), although in modern international criminal law it should be borne in mind that individual responsibility is not linked to a state of war and consequently to the law of war. Therefore it is not unreasonable to say that individuals can be considered subjects of international criminal law.


The primary subjects of international law are therefore States: its norms (which emanate from States) are addressed first of all to States themselves, establishing rights, obligations, powers, faculties, etc. for them. The capacity of these norms to be addressed to States does not depend on a power superior to them, which would determine, in a logic of authority, who their addressees are: a power which – as we know – does not exist.

Unlike internal law, in which the power from which legal norms emanate is also expressed in the sense of imposing and guaranteeing the legal subjectivity of the entities to which it is addressed, in international law the absence of a center of power superior to the basic subjects and endowed with the capacity to impose subjectivity prevents the conception that a hiatus can be produced between the reality of international relations and the law that governs them.

This is the “principle of effectiveness”, the cornerstone of the system. It can be expressed through the observation that international law does not create its basic subjects, it does not determine their subjectivity: it neither regulates nor imposes the requisites, the modalities or the procedures for acquiring the quality of subjects, but limits itself to – so to speak – leaning towards reality, that is, taking note of the factual and historical existence of those actors in international relations that are the States.

In other words, the process of formation (or extinction) of States is not the object of international juridical regulation: the State is formed, transformed or extinguished in social reality, and from when and as long as it actually exists as a State it finds itself the holder of rights and obligations established by norms of the international order.

The acknowledgement of the actual existence of a State (and therefore of its status as a subject of international law) is made by other States through recognition. When a new State is formed, it endeavours to obtain recognition by the pre-existing States, and the latter generally refrain from having regular relations with it until they have recognized it. However, it is agreed today that the international subjectivity of States does not depend on their recognition, but that this has a declarative and essentially political value: whoever grants recognition declares, on the one hand, that he recognizes the other State as actually existing as a sovereign State and, on the other, that he intends to maintain appropriate international relations with it.

So, states are the main subjects of international law; they must have three essential characteristics:

  • having a people: states must exercise their control over a population settled in a given territory and with its own political conscience without the need for homogeneity in aspects such as culture, religion, etc.
  • have a territory: States must exercise their control over a specific territory, however it is not important that the boundaries of this territory are exactly defined, but it is essential to be able to recognize a territorial nucleus in which the states have real control.
  • have real sovereignty over the territory and the people, this category is composed of two types of sovereignty.
    • internal sovereignty: is the ability of a state to exercise its empire within its territory.
    • external sovereignty: is the ability to exercise government over a region and a people independently of interference by other states; the counterpart of this characteristic is the duty of each state not to interfere in the governmental powers of another state. In order for this characteristic to be respected, it is necessary, in short, for the state system to find in itself the source of its own legitimacy, i.e. without being legally dependent on another state. Independence (or external sovereignty) can also be recognized if the State is economically or politically dependent on another State. The important thing, however, is that the state retains its legal autonomy. It is a different matter, however, if the economic dependence is so strong as to result in a real relationship of vassalage between the two states.

More specifically, we can indicate the categories of states which do not have international subjectivity; in this regard, we can recall

  • micro-states: even if the territory is not very large and the population not very numerous, there is no doubt that they are subjects of international law (for example, the Republic of San Marino, the Principality of Liechtenstein, etc.)
  • confederations of states: these can be considered subjects of international law, but in relation to competencies not delegated to the confederative institutions; there is no doubt, however, that the individual states that make them up are subject to international law. By confederation we mean an association of independent states (confederate states) that delegate the exercise of certain powers (usually in matters of defense and foreign policy) to common bodies. A recent example of confederation is Serbia and Montenegro (2003-2006), while the C.I.S. (Community of Independent States) does not constitute a confederation under international law, as the founding agreements and the statute do not delegate particular powers to the organs of the organization, which only have the function of coordinating the policies of the member states.
  • the so-called puppet states: since they do not enjoy external sovereignty, they cannot be considered subjects of international law
  • federated states: they cannot be considered as subjects of international law since they delegate wide powers to the federative institution (typically international and defense competences), thus lacking the characteristic of external sovereignty. For example, the federated states of the United States of America, of the United Mexican States, of the Russian Federation, the Lander of the Federal Republic of Germany, the cantons of the Swiss Confederation (which, although calling itself a confederation, is actually a federation), the provinces of Argentina, etc.
  • Governments in exile: the governments in exile, when speaking of this category we refer above all to the governments that took refuge in England during the Second World War, are not to be considered subjects of international law because they enjoy neither a territory nor the real possibility of exercising sovereignty over the population living there. Nevertheless, with the hope that in the future these governments will regain possession of people and territory, the international acts carried out by these governments can be considered valid. This validity, however, was based exclusively on political and not juridical considerations.

Another valid doctrine tends to consider the state as state-community and state-organization, in order to establish which conception of the state is to be accepted, and leaning towards the latter. It should be noted, therefore, that the State in this case considered is one or more organs of the State itself exercising its own power. According to this line of thought, the international subjectivity of Governments in exile or Liberation Committees cannot be accepted.

International subjectivity

The acquisition of international subjectivity by states, as well as liberation and insurrection movements, is linked to the real manifestation of the three characteristics mentioned above (population, territory, sovereignty) in the head of an organization. Since the international order is atypical, not contemplating a normative and judicial institution, but leaving everything to the free initiative of the states and the agreements that they put in place between them, a procedure for the acquisition of international subjectivity can in no way be outlined. More specifically, the question takes on a mainly political character, insofar as the recognition of a state by another state or by international institutions has only a declaratory function and not a constitutive one, i.e. it is not essential that there be recognition by other subjects for an institution to become a subject of international law.

An adducible example is the State of Israel which exercises control and government over a territory and a population, even though it is not recognized by almost all Arab countries. Furthermore, recognition can be expressed (declared by other states) or tacit (deducible from the beginning of activities of international law having as counterpart the new subject, such as the stipulation of a treaty).

Limits to internal sovereignty

Although it is, in principle, lawful for a State to administer its territory as it pleases, freely organizing the governmental institutions and the laws regulating the civil community, the sovereignty of the same on its territory knows various limitations. These limitations refer in the first place to the prohibition to violate the so-called ius cogens, that is, the set of imperative customs for each state with particular reference to the respect of human rights.

The limits to internal sovereignty are:

  • initiatives aimed at promoting the protection of human dignity;
  • norms on punishment of international crimes (genocide, crimes against humanity, crimes against peace, war crimes);
  • limits on economic and social relations (international economic law);
  • protection of the environment;
  • treatment of foreigners;
  • treatment of diplomats and foreign bodies;
  • treatment of foreign states;
  • treatment of international organizations;
  • rules of international maritime law.

Diplomatic immunity

Another category of limitations concerns the immunity granted to officials of other states. The underlying principle granting extensive protection to diplomatic agents of foreign states is to be found in the custom that institutions of equal rank cannot sue and judge one another (par in parem non habet iudicium). This is reflected in international law in the practice of immunity for diplomatic officials of a foreign state, governed by the Vienna Convention of 1961, which came into force in 1965. This immunity can be divided into functional immunity or personal immunity. Functional immunity applies to acts that the diplomat performs in the performance of his duties and includes:

  • tax exemption (direct taxes);
  • immunity from criminal jurisdiction (excluded for consuls in case of serious crimes);
  • immunity from civil jurisdiction (excluded for real estate or economic activities not owned on behalf of the State for which the official works; it is also excluded for disputes concerning inheritance and succession);
  • personal inviolability (from coercive acts, e.g. police forces);
  • inviolability at home (immunity for traffic violations is not contemplated);

Personal immunity is different. The latter covers the so-called jure gestiones acts of the diplomat, i.e. acts that the official performs as a private individual. In this case the immunity will cover the entire span of his service and will then lapse at the end of his function, once he has left the country, and therefore will make the diplomat liable to prosecution for any offences committed during the period of his functions.


  • Business Law I Essentials. OpenStax.

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