International law
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This article is written by Prateek Singh, from the Institute of Law, Nirma University, Ahmedabad. In this article, he discusses the development of international law and what role does ICJ and India have to play in it.


International Law consists of the rules and principles of general application dealing with the conduct of States and of international organizations in their international relations with one another and with private individuals, minority groups, and transnational companies.

International law

International law is a system of treaties and agreements between nations which regulate how nations communicate with other nations, other nations’ citizens, and other nations’ businesses. Usually, international law falls into two distinct groups:

  • Private International Law

Discusses conflicts between private entities, such as individuals or companies, which have a significant relationship with more than one country. 

  • Public International Law

Deals with relations between nations, these include universal norms of conduct, law of the seas, economic law, diplomatic law, environmental law, human rights law, and humanitarian law. Some principles of international public law are contained in a set of documents, or “codified,” but many are not written down anywhere. 

Sources of International Law

International law comes from various sources, those include:

  1. TreatiesTreaties are expressed agreements, entered into by countries voluntarily, they’re in written form. In interpreting a treaty, the meaning of the terms and the assumption of good faith and good intentions can also play a role. The US ratified the 1970 Vienna Convention on the Policy of the Treaties.

  2. CustomsCustoms are common practices between countries. They are traditional practices that are so expected and consistent that countries operate with the belief that the custom is legally binding and essential. This generally applies to that state as long as a state does not object to customary law.

  3. General Principles of LawThese general principles are developed over a period of time. Legal concepts are an interpretation of how the law will operate on the basis of previous rulings. In addition to looking at previous decisions, international courts can also appeal at judicial judgments for guidance in international law recognition and interpretation.

Treaty of Westphalia

The treaty of Westphalia was signed on 24th October 1648, it marked the end of a war that lasted for 30 years.

The Westphalia area of north-west Germany gave its name to the settlement ending the thirty years’ war, one of the most devastating in Europe’s history. The series of wars began in 1618, and they were all interconnected. The Austrian Habsburgs attempted to impose Roman Catholicism on their bohemian Protestant subjects. It divided the Protestant against the Catholic, the Holy Roman Empire against France, the German princes against the emperor and each other, and France against the Spanish Habsburgs. The Swedes, Danes, Poles, Russians, Dutch, and Swiss all were either dragged in or dived in. Commercial interests and rivalries played a big part and so did religion and power politics. 

The negotiation process was complicated and lengthy. Talks were held in two different cities because each side wanted to meet under its own control on the territory. A total of 109 delegations arrived to represent the belligerent states but at the same time, not all delegations were present. In order to resolve each of the concurrent conflicts, three treaties were signed: the Peace of Münster, the Münster Treaty, and the Osnabrück Treaty. These treaties ended the Thirty Years ‘ War (1618–1648) in the Holy Roman Empire, with the Habsburgs (rulers of Austria and Spain) and their Catholic allies on the one side battling the Protestant powers (Sweden, Denmark, and certain Holy Roman principalities) allied with France (Catholic but anti-Habsburg). The treaties also ended the Eighty Years War between Spain and the Dutch Republic (1568–1648), with Spain officially accepting Dutch independence.

However, the Dutch had not been interested in the actual thirty years war. Westphalia’s Peace established the peace precedent set by diplomatic congress. In Central Europe, a new form of political order emerged, focused on peaceful coexistence between sovereign states. A balance of power had kept inter-state violence in check, and a policy was established against intervention in domestic affairs of another state. The treaty gave Austria’s Swiss independence and Spain’s independence from the Netherlands. The German principalities had their sovereignty secured. Sweden gained land and a cash reward, Brandenburg and Bavaria also made gains and France purchased much of Alsace-Lorraine. The promise of a European Roman Catholic reconquest has long vanished. Protestantism was to live in the country. 

Effect of World war

No strong nations remained on the sidelines in World War I to give effective support to international law, and the concept of third-party arbitration was again threatened; many of the international law’s standing provisions were violated. New ways of warfare presented new problems in the laws of war, but attempts to disarm and ban certain types of weapons (see war, laws of) after the war failed, as shown by the outbreak and course of World War II. The end of hostilities in 1945 saw the world again facing major international issues, including border rectification, refugee treatment, and administration of the territory of the defeated enemy. 

Recent developments

The nuclear age and the age of space introduced new advances in international law. Under the auspices of the United Nations, the space law foundation was established in the 1960s. Treaties to allow the internationalization of outer space (1967) and other celestial bodies (1979) were signed. The Treaty on the Limited Test Ban (see Disarmament, Nuclear) of 1963 banned nuclear testing in the atmosphere, outer space and underwater. The Nuclear Non-Proliferation Treaty (1968) sought to limit nuclear weapons spread. Signed by the United States and the USSR in 1972, the Strategic Arms Limitation Talks Agreements limited defensive and offensive weapons systems.

This was the first of several bilateral arms treaties that were concluded between the two nations before the Soviet Union was dissolved. Other treaties covered Antarctica (1959), narcotic prohibition (1961), satellite communications (1963), and terrorism (1973). The Sea Law Treaty (1982, in effect since 1994) explained the status of territorial waters and the exploitation of the seabed. Environmental problems have culminated in a variety of international treaties, including fisheries agreements (1958), endangered species (1973), ozone layers (1987 and 1992), biodiversity (1992), and global warming (1992 and several years later). There have been several foreign trade deals since the signing of the General Agreement on Tariffs and Exchange (GATT), in 1947.

The European Union (prior to 1993, the European Community) has worked towards creating a national legal system; a Court of First Instance was set up in 1988 to act as a court with original jurisdiction on some economic matters. The creation of the International Criminal Court (2002), which has jurisdiction over war crimes, crimes against humanity and related matters, marked a significant step forward in international law, following the repudiation of the treaty by the United States under President George W. Bush.

Development of International Law by ICJ

There is no provision under the ICJ’s UN Charter or Statute that makes decisions of the ICJ binding, except on the parties. Under art. 38 of Statute of the ICJ, clause 1(d) recognizes the decisions of the ICJ as subsidiary means for the determination of rules of law”:

Art. 38 (1): The Court, whose function is to decide in accordance with international law such disputes as are submitted to it, shall apply-

(d): Subject to the provisions of Article 59, judicial decisions and the teachings of the most highly qualified publicists of the various nations, as subsidiary means for the determination of rules of law.

Furthermore, Art. 59 of the ICJ Law as between the parties limits the applicability of the ICJ ruling, which provides for: 

“The decision of the Court has no binding force except between the parties and in respect of that particular case.”

Such two clauses make it clear that, on the one hand, the ICJ has no general authority to create legislation in the form of a precedent as applicable to courts in many national jurisdictions; on the other hand, the ICJ’s decisions are not a direct source of international law, but there are only subordinate ways of determining the law. But does that mean that the ICJ has absolutely no power to develop or evolve new international law norms? Such an interpretation will frustrate the progressive development of international law and, when resolving disputes, the ICJ automatically introduces or develops new norms when pre-existing rules are not to be enforced. 

ICJ can develop or evolve new rules or norms of international law in the following ways:

  1. ICJ can recognize newly emerged customs– While referring to customary law, the ICJ may find a new practice that has come into force or that has abolished an old custom. This new practice may not have been historically recognized by the international community, but if it has been continuously practiced as an opinio juris, it can be accepted by the ICJ. Often it may accept an instant norm where the subject matter explains the same thing (like cyber warfare) and state practice is predominantly systematic and consistent even if for a short time. The ICJ does not create a rule in such cases, but it is the first to consider a rule that has already been created. 
  2. Reference to General Principles of Law– It was argued that law is created not only by agreement, customs or legislature but also by judges through an interpretation of existing law and the application of general principles of law. Sometimes, when there is no treaty or customary law to rely on, the ICJ may decide its dispute by referring to the general principles of law existing in domestic legal systems. It is likely that states may follow the rule because of the ICJ’s pronouncement, and it will eventually emerge as customary law. In this respect, the ICJ contributes indirectly to the task of making international law.
  3. Making an Entirely New Rule– Renowned jurist James Leslie Brierly has noted that the role of a judge is not merely the implementation of the law but also the formulation of a rule to be applied since complete segregation of legislative and judicial roles can exist only in imagination, not in practice. If there is no source to rely on to decide a particular dispute (no custom, no treaty, no general principle of law), then the ICJ may create a new rule (although it may not expressly state that it acknowledges a new rule) that may be based on equity, justice, and other relevant factors to reach a fair solution in a particular dispute. 

Development of International Law in India

India’s contribution to international law can not be overemphasized, especially in the fields of humanitarian law, environmental conservation, and security, technology and trade laws. At the same time, to meet its international obligations, India has harmonized many of its domestic laws with international standards and norms. People’s rights, environmental rules, intellectual property rules, arbitration laws, trade laws, and space laws are important in this exchange. Implementing international law in India can be viewed either from the viewpoint of the position of each government or from the standpoint of each area of law. 

The linkages between India’s Constitution and foreign law date back to the days of pre-independence. Even during British rule, India was the League of Nations’ separate member. It is also a founding member of the UN. The Preamble includes many core principles and philosophies that India promises to its people and as a country aims to achieve. Among other things, the Preamble states that social, economic, and political justice must be guaranteed for all people and that freedom and equality will be promoted. Such principles are the foundation of true democracy and their essence is fundamental. Every nation strives to achieve them.

It is possible to equate the human rights in Part III and the substantive directives to the State in the form of Directive Principles in Part IV with the Universal Declaration of Human Rights (UDHR) and to identify commonalities. The United Nations Organization (UNO) was established as an international body to avoid the collapse of the Third World War, to maintain international peace and stability and to uphold human rights. Having that purpose in mind, on 10 December 1948 the nations came together and adopted and ratified the Universal Declaration of Human Rights. It should be remembered that the Indian Constitution adopted on 26 November 1950 influenced greatly the history of the human race and the principles sought to promote and preserve the Universal Declaration of Human Rights. 

Article 51A gives effect to the resolution found in Article 29(1) of the Universal Declaration of Human Rights, which stresses the obligations of individuals to the general community. Such responsibilities support society and also assist in the individual’s complete flourishing. Indian Constitution is one of the few constitutions in the world which expressly provides for fostering international relations. 


International law, divided into two parts as mentioned above, plays a major role in governing the countries of the world. International law is a law that is always in the developing process because there is so much new input and progress made by the world which has to be inculcated so that it caters to everyone around the globe.


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