860 multilateral conventions on Environmental Law, Human Rights, Humanitarian Law and Law of the Sea
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Introduction to International Law

International law is made up of the entirety of the legal principles and norms which govern the international community (States and international organisations). Initially, International Law dealt only with the obligations between States but has since evolved , progressively making room for the growing participation of international organisations, groups, persons and issues, such as the environment. In some cases, especially where the European Convention on Human Rights is concerned, individuals are not only beneficiaries of the aforementioned law, but can also lodge a complaint against the State that infringes upon their rights. International Law has a number of sources: treaties, customary law, general principles of law, precedents and doctrine.

Principles of State sovereignty and non-intervention:

Each State is sovereign over its territory and freely decides its own laws and its path to development. As a matter of principle, no State should intervene in the internal affairs of another State.

However, four limitations prevail:

Treaties and Conventions: States may commit themselves voluntarily to respect certain obligations through the adoption of the treaties or international agreements. These are texts outlining a number of obligations that the States have ratified, and whose implementation may entail more limiting legal mechanisms.

Jus Cogens: The international community considers certain principles universal. These are the peremptory norms of Jus Cogens which forbid slavery, genocide, piracy, apartheid or war, as well as treaties which would interfere with fundamental Human Rights. According to article 53 of the 1969 Vienna Convention on the Law of Treaties (VCLT hereinafter), a peremptory norm of International Law is a norm that has been accepted and recognised by the international community as a norm for which no derogation is allowed, and which can only be modified by the adoption of a new norm of International Law endowed with the same normative characteristic. Peremptory norms have a particular the conviction that no breach is permissible for a norm of International Law (Opinio Juris). A variation of the norm of Jus Cogens renders the treaty void and involves the responsibility of the State. Such norms may place limitations on a State’s contractual freedoms. The adoption of a treaty can also be hampered if it violates a peremptory norm of International Law.

Declarations: Within the context of the United Nations General Assembly or international conferences, States may adopt norms through declarations that recognise certain principles. Such declarations have moral significance but are not legally binding.

International Customary Law: Certain norms and obligations are derived from international customary law (ICL hereinafter). ICL has two sources of origin: the habitual practice of States and Opinio Juris (or legal opinions), by which States are convinced that such behaviour constitutes a legal obligation. There is therefore a material element which, in practice, is associated with the State (the practice of an international organisation can also evolve into normative customs). This practice must be ongoing, recurrent and general. The second element is psychological: it is the conviction that practice mirrors a corresponding obligation. Custom emerges when one or more States, through repeated acts, acknowledge(s) a right or a norm by its regular and protracted occurrence. Thus, the States in question are obliged to respect this norm, even in the absence of a reference in writing. Furthermore, some articles from certain conventions acquire the value of a customary norm or even lead to the establishment of customary law, thus codifying it into a body of written rules.

Making a Treaty or a Convention:

A treaty or a convention bears similarities to a contract between two or more States. In principle, a treaty binds only the States that have ratified it.

The conclusion of a treaty is carried out in four stages:

Negotiations may come under different forms. While negotiations for bilateral treaties are straightforward and take the form of written correspondence, multilateral treaties are drawn up during an international conference with States negotiating directly or through an international organisation. These negotiations usually end with the adoption of the text of the treaty (preamble, legal provisions, annexes...)

Signature (Article 12, VCLT)
During the adoption phase, the signature shows that a treaty has been approved. In multilateral treaties, the text is adopted within the framework of an international conference, upon being signed by the State representatives. The State signs the agreement through its diplomats or a member of its government to show its approval of the principle. The signature is not legally binding except in the case when it is stipulated by the treaty (article 12 para. 1 VCLT). From then on, the State is morally obliged to abstain from any act that would defeat the object and purpose of the treaty (article 18 VCLT). In practice, only a full signature (or a signature ad referendum) of a treaty obliges the State to apply the convention. In other cases, the signature of a representative will require further ratification.

Ratification, acceptance, approval and accession (article 14 VCLT)
States give their consent to be bound by a treaty most commonly by exchanging instruments of ratification. Most countries will set up an internal procedure to ratify the agreement. Certain governments have to submit the convention to their highest institution, such as parliament, for approval. Once the treaty has been internally approved, the government can ratify the convention, which by so doing it commits itself to observe and put into practice.
In the instance of its absence during the negotiations, a State may bind itself to a treaty through accession, rather than through ratification, acceptance and approval.

Entry into Force (Article 24 VCLT)
In the case of a bilateral treaty, this will enter into force upon the exchange of instruments of ratification. A multilateral treaty enters into force after a certain number of ratifications or upon a date set by the treaty. After a treaty has entered into force, it becomes binding upon the States that have ratified it. In some instances, the treaty grants additional time (usually 1 to 3 months) after ratification to enable the State to apply the convention. The State bears full responsibility for the violation of a treaty, as per the latin dictum “pacta sunt servanda”.

Nota bene: the expression used by a State to show its commitment to the treaty may vary according to the treaty. In some cases, the procedure is stipulated by the treaty. In other cases, it is the 1969 Vienna Convention on the Law of Treaties that defines the procedure which must be followed for the completion and entry into force of a treaty.

Reservations (Articles 19 to 23 VCLT)
States can give their “reservations” upon signing or ratifying a treaty. Reservations are unilateral statements whose aim is to exclude or modify the bearing of a legal provision. The State may, for example, commit itself to respect the convention with the exception of certain articles, which it may deem in conflict with its internal law. The reservations can only be made within the context of a multilateral treaty. The reservation is made in writing and notified to the other contracting States. There are three limitations in affecting reservations: the treaty may exclude reservations; it may also prohibit certain types of reservation; the reservation must not be incompatible with the goals and purposes of the treaty.
The aim of the reservation is to exclude or modify parts of the treaty by the author of the reservation of the “reserving State” (article 21 para 1a VCLT). The other negotiating States may demonstrate their approval of a reservation if 12 months lapse without them formulating an objection to it. The acquiescence of the other States enables the reserving State to proceed with the conclusion of the treaty. Conversely, should another State object to the reservation, it becomes the “objecting State”.

Interpretive Declaration
An interpretive declaration is a unilateral statement which clarifies the meaning or the scope of a legal provision of the treaty. An interpretive declaration can be made at any time, unlike reservation which can only be made upon signing or ratifying a treaty. In practice, States frequently make interpretive declarations which are akin to a “hidden reservation”.

Further readings

The Swiss Federal Department of Foreign Affairs publishes a useful ABC of Human Rights available online.



According to the Office of the High Commissioner for Human Rights, 'Human rights are rights inherent to all human beings, whatever our nationality, place of residence, sex, national or ethnic origin, colour, religion, language, or any other status. We are all equally entitled to our human rights without discrimination. These rights are all interrelated, interdependent and indivisible.'

Definition of Human Rights
On principle, Human Rights are universal. 'Universal' means that UN Member-States have the duty to promote and protect these rights regardless of their political, economic and cultural systems. Futhermore, Human Rights are inalienable, in the sense that they can not be taken away.
The International Bill of Human Rights set Human Rights treaties up. It includes: Universal Declaration of Human Rights, the International Covenant on Civil and Political Rights and its two Optional Protocols as well as the International Covenant on Economic, Social and Cultural Rights. The notion of 'Interdependent and indivisible' means that rights are interrelated, thereby the improvement of one right facilitates advancement of the others, and vice-versa.
In addition, Human Rights are equal and non-discriminatory. This principle prohibits discrimination based on a non-exhaustive list of categories ' such as race, colour, sex, language, religion, political or other opinion, national or social origin, property, birth or other status '. (Art. 2 of Universal Declaration of Human Rights).
States take on obligations and duties under International Law to respect, to protect and to fulfil Human Rights. When a State ratifies international treaties, it commits itself to take all necessary actions to implement Human Rights as well as to adopt national rules in compliance with international agreements.

Implementation of Human Rights
There are four mechanisms to strengthen and implement Human Rights: legal, political, diplomatic and civil society instruments. However, the implementation of Human Rights comes primarily under the responsibility of legal and administrative institutions of the State. In addition, Human Rights treaties each contain a specific mechanism for implementation. The main legal instruments are:

  • UN Conventions require States to submit regular reports on the Human Rights situation in their territories. Nevertheless, these reports have no legal value, but only political reach in order to oblige States to justify their actions to the international community. Several of the  Council of Europe's conventions also require States  to submit a report.
  • The European Court of Human Rights provides for an individual right of appeal for the victims of Human Rights violations. A victim can, after all domestic remedies have been exhausted, give an application against one of the High Contracting Party of the rights set forth in the Convention or the protocols thereto (art 34 and 35 of Convention for the Protection of Human Rights and Fundamental Freedoms).
  • ' State to State complaint allows a State to lodge an official complaint against another State Party for Human Rights violations '. However, this procedure is only a mediation without the possibility of a binding decision in the case of failure. Although the majority of conventions has ' State to State complaint ' mechanism, States have never used this instrument. Indeed, they want to preserve their foreign relations.
  • International criminal tribunals are in charge of prosecuting and punishing those responsible for the most serious human rights violations such as genocide. Moreover, there is two international ad hoc tribunals: the International Criminal Tribunal for the former Yugoslavia and for Rwanda as well as the Special Court for Sierra Leone. These tribunals were established for the prosecution of the most serious crime committed in clearly defined conflicts.

The Human Rights Council and the Office of the High Commissioner for Human Rights
The Office of the United Nations High Commissioner for Human Rights (OHCHR) was created in 1993 by a resolution of the UN General Assembly . It ' represents the world's commitment to universal ideals of human dignity ' and its mandate is to promote and protect all Human Rights. To this end, the OHCHR can rely on the Human Rights Council as well as the core treaty bodies for promoting the universal ratification and implementation of international treaties concerning Human Rights. The OHCHR's priorities are set out in two key strategic documents: the OHCHR Plan of Action and its Strategic Management Plan 2010-2011.
The Human Rights Council was created by the UN General Assembly in 2006 ' with the main purpose of addressing situations of Human Rights violations and make recommendations on them '.The Council is an inter-governmental body composed of 47 States responsible for the promotion of Human Rights. In 2007, the Human Rights Council introduced the Universal Periodic Review mechanism which aims to ' assess the Human Rights situations in all 192 UN Member States '. Furthermore, an Advisory Committee was created in order to provide a deep expertise on thematic Human Rights issues. In addition, a complaint's procedure mechanism ' allows individuals and organizations to bring complaints about Human Rights violations to the attention of the Council '.

Further readings

The Swiss Federal Department of Foreign Affairs publishes a useful ABC of Human Rights available online.



According to the International Committee of the Red Cross (ICRC), International Humanitarian Law ' protects persons who are not or are no longer participating in the hostilities and restricts the means and methods of warfare '. Its fonctions are twofold: first, to regulate the conduct of hostilities, and secondly, to protect the victims of armed conflict. International Humanitarian Law is also known as the 'law of war' or 'the law of armed conflict'. Moreover, it is proper to distinguish ' jus ad bellum (that is the set of rules of International Law relating to the conditions in which a subject of International Law is permitted to resort to armed force) from jus in bello (that is, the set of rules of International Law applicable to the mutual relations of parties to an international armed conflict, or more briefly the laws and customs of war) '. However, International Humanitarian Law does not include jus ad bellum but only jus in bello. In 1945, the Charter of the United Nations established that Member States shall abstain, in their international relations, from resorting to the threat or use of force (art. 2.4 of the Charter of the United Nations). Thus, the  Charter of the United Nations introduces the notion of Jus contra bellum that is the law on prohibition of war. Today, many regulations are accepted by the majority of States and are, therefore, regarded as an integral part of customary law.
Conventions concerning International Humanitarian Law

  • The Hague Conventions concerns the conduct of hostilities. These conventions introduce  regulations to limit the means and methods of warfare such as the Declaration of 1899 banning the use of poison gas and ' dumdum ' bullets. These conventions were elaborated at the International Peace Conference of 1899 and 1907.
  • The four Geneva Conventions of 1949 contain provisions for the protection of victims of armed conflict. The first Geneva Convention was introduced in 1864 by the International Committee of the Red Cross created by Henri Dunant. Its aim is to provide ' protection for the wounded and sick, but also for medical and religious personnel, medical units and medical transports '. In addition, it recognizes the protection of the distinctive emblems. In 1949, the second Geneva Convention was adopted and replaced Hague Convention of 1907 for the Adaptation to Maritime Warfare of the Principles of the Geneva Convention. This Convention applies specifically to wounded, sick and shipwrecked military personnel at sea during war. The third Geneva Convention of 1949 regulates the right of prisoners of war. It replaced the Prisoners of War Convention of 1929, broadening the categories of persons entitled to prisoner of war status. Moreover, ' the Convention establishes the principle that prisoners of war shall be released and repatriated without delay after the cessation of active hostilities '. Finally, the fourth Geneva Convention of 1949 takes account of the experiences of World War II and integrates protection of civilians, including in occupied territory, in the norms regulated by international humanitarian law. ' The bulk of the Convention deals with the status and treatment of protected persons, distinguishing between the situation of foreigners on the territory of one of the parties to the conflict and that of civilians in occupied territory '.
  • The Additional Protocols to the Geneva Conventions: in 1977, two Additional Protocols strengthened the protection of victims of international (Protocol I) and non-international (Protocol II) armed conflicts. Protocol II responds to the increase of civil wars and national liberation wars. In 2005, a third Additional Protocol on the adoption of an additional distinctive emblem, such as ICRC symbol, was adopted.

To whom does International Humanitarian Law apply?
International Humanitarian Law applies only to international and non-international armed conflicts. A distinction is made between international armed conflicts in which at least two States are engaged and non-international armed conflicts which refers to conflict on a single national territory between regular armed forces and identifiable armed groups, or between armed groups fighting one another (Art. 3, common to the four Geneva Conventions).
International Humanitarian Law protects the people who do not take part actively in the fighting, such as civilians, wounded, medical and religious military personnel. In addition, it also protects those who have ceased to take part in the hostilities, such as prisoners of war, sick combatants and soldiers. In this instance, International Humanitarian Law prescribes that ' these categories of person are entitled to respect for their lives and for their physical and mental integrity. They also enjoy legal guarantees '. In addition, specific regulations prescibes decent conditions of detention for prisoners of war.

To limit the effects of armed conflict, International Humanitarian Law forbids all means and methods of warfare which:

  • fail to discriminate between those taking part in the fighting and those who do not
  • cause superfluous injury
  • cause severe damage to the environment

The implementation of International Humanitarian Law
States must teach humanitarian rules to their armed forces as well as to the general public.  Futhermore, they have to implement preventive measures against International Humanitarian Law violations. To this end, governments must sanctions in case of the most serious violations such as war crimes. States must also pass laws to protect the red cross emblems.
At international level, two International Criminal Tribunals were created in the aftermath of the conflicts which took place in former Yugoslavia and Rwanda. In 1998, The International Criminal Court of the Hague was established by Rome Statute, with the responsibility of repressing inter alia war crimes.

The difference between Human Rights and International Humanitarian Law
Although, some of their rules are complementary, Human Rights and International Humanitarian Law constitute two distinct parts of International Public Law. International Humanitarian Law applies only in situations of armed conflict, while Human Rights apply to all human beings at all times. Nevertheless, some Human Rights provisions can be suspended in war time.

Further readings

The Swiss Federal Department of Foreign Affairs publishes a useful ABC of Human Rights available online.



International Environmental Law is a recent development in International Law which takes its roots in the early 1970s. Indeed, the notion of natural resources’ preservation made its appearance during the United Nations Conference on the Human Environment of Stockholm of 1972 in which ecological issue was raised at international level. According to the Stockholm Declaration, 'the natural resources of the earth, including the air, water, land, flora and fauna and especially representative samples of natural ecosystems, must be safeguarded for the benefit of present and future generations through careful planning or management, as appropriate.' (Principle 2 of Stockholm Declaration). The International Legal Search Engine 'WhatConvention.org' completes the definition of Environmental Law with the notion of the Law of the Sea, as well as human and animal health. The Law of the Sea should be define as: 'a comprehensive legal framework to regulate all ocean space, its uses and resources'.
The following important development is the Earth Summit which took place in Rio de Janeiro in 1992. At this occasion, States reiterated theirs commitments for environmental protection as well as the necessity to promote sustainable development. According to the Rio Declaration, Environmental Law and sustainable development are two rights specific to human beings: 'Human beings are at the centre of concerns for sustainable development. They are entitled to a healthy and productive life in harmony with nature' (Principle 1 of Rio Declaration). Therefore, some doctrines consider that Environmental Law is an integral part of Human Rights.

The implementation of Environmental Law
States have the duty to take measures for the implementation of Environmental Law and are bound to make ecological damages to neighbouring states. Indeed, the Stockholm Declaration recommends several instruments which enable to safeguard the implementation of Environmental Law such as scientific cooperation, informations exchange and the respect of the principle of 'good neighbourhood'.

In addition, the Customary Law establishes some fundamental principles specific to Environmental Law:

  • The precautionary principle involves that the absence of scientific consensus cannot stop the adoption of regulations preventing environmental damages.
  • The polluter pays principle introduces that 'the polluter should, in principle, bear the cost of pollution, with due regard to the public interest and without distorting international trade and investment.'(principle 16 of Rio Declaration). In order to do so, States have three main implementation instruments: norms, taxes and sanctions. The purpose of these mechanisms is to dissuade the polluter to pollute more in order to reduce his cost.
  • The prevention principle is the core instrument of Environmental Law. Indeed, Environmental Law aims most and foremost to prevent the deterioration of the ecosystem on Earth. 'The precautionary principle invites pollution prevention measures even if the risk or the scope of the damage is uncertain.' This principle is particularly important because the damages caused to the nature are very often irreversible.
  • The principle of correction of environmental harm at source differs from the prevention principle because its purpose is based on 'the principle that environmental damage should as a matter of priority rectified at source'.
  • The integration principle 'requires that due consideration be given to the potential consequences of environmentally fateful decisions'. Governments should take ecological issues into account in their decisions-making processes. This transversal approach of Environmental Law was recognised by the Rio Declaration.
  • The principle of access to information and public participation ensures that ordinary people have access to information concerning environment and the use of harmful substances. The Aarhus Convention of 1998 grants this right regarding access to information, public participation and access to justice. Indeed, the purposes of Aarhus Convention is treefold: first, 'ensuring public access to environmental information held by the public authorities'. Secondly, 'fostering public participation in decision-making which affects the environment'. Finally, 'extending the conditions of access to justice in environmental matters'.


The law of the sea is defined as the “totality of rules of international law which determine the status of maritime spaces and establish a regime for activities taking place in these spaces”.
This legal branch deals with maritime spaces as traffic routes as well as fish reserves and its jurisdiction includes the seabed and subsoil as well as natural resources they contain. Of customary origin, the law of the sea is one of the most ancient branches of international law.
Seas are defined as naturally and freely interconnected saline water spaces around the globe, (as opposed to fresh inland waters). Seas are spaces of exchange and confrontation and are economically and strategically important for States. This entails a need for a legal regime governing the management of these spaces.

Since the antiquity, jurists are concerned with the status of maritime spaces. The latter constitute in fact a simple and quick transport route for people as well as goods and is an important source of revenue for coast dwellers of riparian States. Until the 17th century, the absence of a legal regime and diverging claims of States to maritime spaces resulted in the sea being a space where every State was able to act at its whim. This required thus the elaboration of a legal regime for these coveted spaces. Progressively, the conviction gained ground that conflicting territorial claims were harming rapidly increasing commercial interests. Yet two differing basic principles could be envisaged: Should maritime spaces be divided among States and subjected to their sovereignty? Or should one opt for a regime of freedom of the seas? The latter was proposed for the first time during the 17th century by Hugo Grotius and finally prevailed. Oceans and seas were thus considered to be spaces open to everyone and free from any attachment to State territories, with the exception of a 3 miles strip counted from the shore, which was considered to be a part of the costal State’s territory. The law of the sea started thus developing based on a compromise between the freedom of the seas and the maritime extension of territorial sovereignty.
Only during the twentieth century that the proliferation of competing territorial claims on the seas pushed the international community to develop a common system to ease tensions between states.

During the first United Nations Conference on the Law of the Sea (UNCLOS I), held in Geneva from 24 February to 27 April 1958, the law of the sea is codified for the first time. Four conventions have been adopted:

  • Convention on the Territorial Sea and the Contiguous Zone, 29 April 1958
  • Convention on the High Seas, 29 April 1958
  • Convention on Fishing and Conservation of the Living Resources, 29 April 1958
  • Convention on the Continental Shelf, 29 April 1958

Despite a low number of ratifications, they enter into force between 1962 and 1966.
A second conference on the Law of the Sea was established in 1966 but covered only the case of the territorial sea.

A third conference on the law of the sea (UNCLOS III) is held under the auspices of the UN from 1973 to 1982 in Montego Bay (Jamaica). It adopted the United Nations Convention on the Law of the Sea (UNCLOS). The convention, which includes nine annexes, has entered into force on the 16th November 1994 after ratification by 60 States. It revisits and summarizes the law of the sea as codified in the Geneva Conventions of 1958 and further develops provisions regarding maritime zones that have been defined earlier, such as the territorial sea, the contiguous zone, the high seas and the continental shelf. In addition, it develops provisions regarding the following newly defined zones:

  • archipelagic waters
  • the exclusive economic zone
  • straits for international navigation
  • the international seabed area and its subsoil

The United Nations Convention on the Law of the Sea creates a legal framework within which all activities relating to seas and oceans are regulated.  It also establishes rights and obligations for States parties relating to navigation, the use of living and mineral resources, the protection and preservation of the marine environment as well as scientific research, within all zones defined by the Convention.

The convention also establishes an International Tribunal for the Law of the Sea, an independent jurisdictional body based in Hamburg. The Tribunal’s function is to settle disputes that may arise from issues related to the interpretation and the application of UNCLOS. It can be seized by States parties to the Convention as well as other entities (States and international organisations which are not parties to the Convention as well as individuals and legal entities) whenever the Convention provides for such a case. In addition, the Tribunal can be seized if another agreement establishes the competence of the Tribunal.

This general regime established by the Convention of 1982 is completed by a multitude of international treaties that deal with more specific issues within the law of the sea. Examples are conventions on biological diversity or on the protection of underwater cultural heritage. Some of these treaties apply on a global, other only on a regional level. These conventions aim at elaborating a more complete legal framework covering fields such as the protection of the marine environment, the management and exploitation of natural resources, the delimitation of maritime spaces, the regulation of navigation and fishing or the prevention and progressive elimination of marine pollution.

A branch of law in constant evolution, the law of the sea constitutes nowadays a complete legal framework adequate for regulating all issues related to maritime spaces.