Sources of International Law

References• Article 38(1) of the Statute of the International

Court of Justice• D. J Harris, Cases and Materials on

International Law, Chapter 2• Malcolm N. Shaw, International Law, Chapter 3• H. Thirlway, The Sources of International Law,

in M. Evans 9Ed.) International Law• Professor Christopher Greenwood, Sources of

International Law: An Introduction

International law

International lawPrimary

rules:body of

principles and rules that lay

down the rights and obligations

of the subjects of

that system

Primary rules:

body of principles and rules that lay

down the rights and obligations

of the subjects of

that system

Secondary rules:rules that can be

applied to determine what are the primary rules, how they

come into existence and how

they can be changed (sources)

Secondary rules:rules that can be

applied to determine what are the primary rules, how they

come into existence and how

they can be changed (sources)

Material sources: The place (normally

document) in which the terms

of the rule are set out eg. Treaty, resolution of

UNGA

Material sources: The place (normally

document) in which the terms

of the rule are set out eg. Treaty, resolution of

UNGAFormal sources:

The question of the authority for the rules as a rule of law binding

on states(Art 38 ICJ Statute)

Formal sources:The question of the

authority for the rules as a rule of law binding

on states(Art 38 ICJ Statute)

• A rule must come from somewhere, as well as the idea that there is a flow, a process which may take time: a rule may exist conceptually, as a proposal or a draft, and later come to be accepted as binding

• Where does international law comes from and how is it made?

Article 38 of the Statute of the International Court of Justice

The Court, whose function is to decide in accordance with international law such disputes as are submitted to it, shall apply:

a) International conventions, whether general or particular, establishing rules recognized by contesting states;

b) International custom, as evidence of a general practice accepted as law

c) General principle of law recognised by civilised nationsd) Subjects to the provisions of Article 59, judicial decisions

and the teachings of the mostly highly qualified publicists of the various nations , as subsidiary means for the determination of rules of law

Art. 38(1) of the ICJ Statute

Art. 38(1) of the ICJ Statute

International treaties and Conventions

International treaties and Conventions

Subsidiary Sources

1.Judicial decisions2.Legal teaching

Subsidiary Sources

1.Judicial decisions2.Legal teaching

International custom

International custom

General principles

of law recognized by civilized

nations

General principles

of law recognized by civilized

nations

Custom• “States behave to each other in given circumstances

in certain ways, which are found acceptable, and thus tacitly assented to, first as guide to future conduct and then, little by little as legally determining future conduct”

• Asylum Case‘the party which relies on a custom of this kind must prove that this custom is established in such manner that it has become binding on the other party’- must prove that the rule invoked by it is in accordance with a constant and uniform usage practised by the states in question

Customary International Law-elements

Customary International Law-elements

Established, widespread and

consistent practice on the part of states

Established, widespread and

consistent practice on the part of states

Psychological element

(opinio juris)

Psychological element

(opinio juris)

• No particular duration is required for practice to become law provided that the consistency and generality of a practice are proved-North Sea Continental Shelf Case (1969)

• Legality of Nuclear Weapon Case ‘the substance of customary law is to be found

primarily in the actual practice and opinio juris of states’

• The mere fact of consistent international practice in a particular sense is not enough. Additional elements are needed:-a) an established, widespread and consistent practice on the part of statesb) psychological element known as the opinio juris necessitatis

• North Sea continental Shelf Case‘not only must the acts concerned amount to a settled practice, but they must also be such, or be carried out in such a way, as to be evidence of a belief that this practice is rendered obligatory by the existence of a rule of law requiring it’-opinio juris

o Opinio juris-deduced from the state’s pronouncements and actions

• If a claimed based on general customary law sufficient to establish that the rule, there is no need to show that the other party has accepted it, or participated in the practice unless:-

a)Rules of special/ local customary lawCase: Right of passage over India Territory

b)Persistent objectorCase: Fisheries (United Kingdom V Norway)Case: Asylum (Colombia/Peru)

• State object consistently to the application of a rule of law while it was still in the process of becoming such rule could ‘opt out’ before the rules established

• The persistent objector principle allows a State which has persistently rejected a new rule even before it emerged as such to avoid its application.

Treaties and conventions in force• A treaty is a written agreement between

states or between states and international organizations, operating within the field of international law

• Governed by the Vienna Convention on the Law of Treaties of 1969 and the Vienna Convention on the Law of Treaties between States and International Organizations and between International Organizations 1986

• Maybe multilateral (bind many states) or bilateral (binding on two states)

• The binding nature of treaties is based on the principle of pacta sunt servanda-what has been agreed to must be respected ( Every treaty is binding upon the parties to it and must be performed by them in good faith [Art. 26 VCLT 1969])

• A treaty does not create obligations or rights for third State without its consent-subject to two apparent principles:

a)Treaty becomes and obligation of general customary international law

b)State not a party accept obligation and benefit from the treaty

• Many treaties are authoritative statements of customary law (writing down what were previously unwritten rules of customary law).

• Example of a treaty provision intended to be codificatory of the existing law is the Vienna Convention on the Law of Treaties, 1969 (VCLT). Courts treated main provisions of VCLT as codification customary law and applicable to all States whether they are parties to the Convention or not.

North Sea Continental Shelf caseso Issue:-what principles and rules of international law

applicable to the delimitation as between the parties of the areas of the continental shelf in the North Sea

o Denmark and the Netherlands argued that the equidistance principle as stated in Article 6(2) of the 1958 Geneva Convention on Continental Shelf applied (crystallised customary international law)

o Held-the provision concerned should be of a fundamentally norm-creating character such as could be regarded as forming the basis of a general rule of law

‘Although the passage of only a short period of time is not necessarily, or of itself, a bar to the formation of a new rule of customary international law on the basis of what was originally a purely conventional rule, an indispensable requirement would be that within the period in question, short though it might be, State practice, including that of States whose interests are specially affected, should have been both extensive and virtually uniform in the sense of the provision invoked; - and should moreover have occurred in such a way as to show a general recognition that a rule of law or legal obligation is involved.’ (ICJ Reps, 1969, p. 43)’

• State practise emerge when a large number of States ( include states that are not parties to the treaty) agree upon a treaty provision and subsequently apply the treaty provision

• it can become part of customary international law, eg treaty concluded to prohibit war, terrorism, diplomacy, treaty-making

Categories of treaties

ContractualTreaties of contractual

nature between states governing matters such as

trade, extradition, air

and landing rights and

mutual defence

ContractualTreaties of contractual

nature between states governing matters such as

trade, extradition, air

and landing rights and

mutual defence

ConstitutionalThe Charter of the United Nations is a treaty to which all

member states are party and which serves as the constitution of the United Nations

ConstitutionalThe Charter of the United Nations is a treaty to which all

member states are party and which serves as the constitution of the United Nations

LegislativeTreaties entered between states

which codify existing rules of

customary international law or which create new rules of law

LegislativeTreaties entered between states

which codify existing rules of

customary international law or which create new rules of law

The general principles of law• International tribunals may refer to the

general principles of law (common principles of law found in municipal states) when there are no rules of treaty or customary law applicable.

• Eg. Circumstantial evidence (Corfu Channel Case), reparation for breach of undertaking (Chorzow Factory Case),estoppel (Temple of Preah Vihear), Res Judicata (Effect of Awards Made by the UN Administrative Tribunal)

• English system of trusts and continental institution of mandate (International Status of South West Africa Case)

• the legal personality of corporations (eg in the Barcelona Traction Co. case (1970))

Subsidiary Sources1. Judicial precedent International tribunals may refer to judicial decisions

as means to determine applicable rules of law subject to article 59 of the Statute of IJC which stipulates that:‘the decision of the Court has no binding force except between the parties and in respect of that particular case’

Include the decisions of the municipal courts• Useful statement of international law on a

particular point• state practice on question of customary

international law

2. Text writings• The teachings of the most highly qualified

publicists are subsidiary means of determination of law

• Opinions of eminent legal writers such as Vattel, Grotious, Bynkershoek, or vittoria during the early days of development of international law

The relationship between the sources of International Law

Relationship between treaty and custom

• Treaties may serve as acts of practice significant for the development of custom

• North Sea Continental Shelf:-1)Declaratory of existing rule2)“Crystallizing effect” on the customary rules3)Applied by non state parties (must be norm

creating character)

• Military & Paramilitary activities in and against Nicaragua (Nicaragua v United States of AmericaIssue:-whether the customary rules on armed force and the intervention continued to bind the parties parallel with the obligations under the UN Charter and other treaties they had accepted.

Held:-There are no grounds for holding that when customary international law is comprised of rules identical to those of treaty law, the latter supervenes the former, so that the customary law has no further existence of its own

The Hierarchy of sources

• If a treaty rule or a customary rule exists, then there is no need to refer to general principles of law

• Art 38 does not indicate whether there was hierarchy of application between custom and treaty

• If a treaty is lex specialis, it will prevail over any inconsistent rules of customary law

Possible new or additional sources

Unilateral acts

• In the Nuclear Tests Case, the Court held that France had assumed legally binding obligations through unilateral declarations, made to the world at large, to the effect that it would not hold any further atmospheric nuclear tests in the Pacific

Resolutions of the UN General Assembly

• Many resolutions of UNGA are material sources of law

• Disputable whether tantamount to independent source of law

• Based on decided cases, resolutions by UNGA only declaratory of customary law or evidence of opinio juris

Security Council Resolution• Decisions taken by the Council under Chapter VII of

the Charter and framed in mandatory terms are legally binding on all States (Article 25 of the Charter).

• Under Article 103 of the Charter the duty to carry out a decision of the Council prevails over obligations under all other international agreements (see the Lockerbie cases (1992)).

• However, the Council does not create new laws but rather obligations in relation to specific issues and it is not a legislature (see the decision of the ICTY in Tadic (1995)).

International Law Commission

• The studies of international law produced by the International Law Commission for the General Assembly, especially if adopted by the Assembly, may also have an important effect on customary international law, even if they are not turned into treaties (the ILC Articles on State Responsibility adopted in 2001 are a good example)

‘superior norms’• The concept of jus cogens-the category of

‘peremptory’legal norms, norms from which no derogation by agreement is permitted

• The status of peremptory norm derives from the importance of the content of the norm to the international community

• Eg. Prohibition on genocide• Asimilate to create ‘obligations erga omnes’-

obligations which are regarded as owed to the whole international community

• The right to react to any violation of the norm is not confined to the states directly injured by the violation but appertains to every state

Barcelona Traction

‘an essential distinction should be drawn between the obligations of a state towards the international community as a whole and those arising vis-avis another state in the field of diplomatic protection. By their nature, the former are the concern of all states. In view of the importance of the rights involved, all states can be held to have a legal interest in their protection : they are obligation erga omnes’

• Outlawing the acts of aggression• Genocide• Protection from slavery• Racial discrimination