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Week 3 – Sources of International Law

Statute of ICJ stipulates sources:

38(1) The court ... shall apply:

• Treaties
• Custom
• General Principles of Law
• Judicial Decisions
• Learned Writers

criteria modified by:

Article 38(2)
• despite 38(1) court can decide a case on basis of equity if parties agree – never used

Article 59
• decisions of Court have no binding force except between parties and in respect of particular case
• treaties, custom, & general principles constitute legally enforceable rights & duties (lex lata)
• other sources constitute non-binding sources of law, or law in formation (lex ferenda)

Questions arising from this range of sources:
"Is this list exhaustive?"
"Is there an implicit hierarchy impled in 38(1)?"
"What is the interrelationship between sources?"

ICJ Jurisdiction over Contentious Cases

In all cases, ICJ jurisdiction rests on consent; however, once jurisdiction is established, parties are bound to abide by outcome

• Comprimis/Special Agreement
• Unilateral Application
• Operation of Treaty
Treaties and Conventions

Definition:
• deliberate act that creates international law – treaties show what states are willing to do
• agreements between two or more states or other ‘legal persons' with rights and powers equivalent to states in IL (i.e. international organizations)
• can be result of compromise, bargaining (rights traded for rights), or may be peace treaties made under the compulsion of force/war

Use of treaties: to finalize agreements between:

• states and states
• states and IOs
• between IOs

Treaties may codify, define, interpret, or abolish existing customary or conventional rules of international law or create new rules
• often entered into because customary practice too restrictive
• treaties therefore a vehicle of transformation of IL (not conservative)

Four Major Rules of Interpretation
• intentions of the parties
• specific prevails over general
• practices of states should not derogate from treaties
• bilateral treaties are like contracts because they create legal obligations that prevail over general international law

Reasons for binding effect:

• shared sense of commitment
• if one country does not respect its promises, other countries may not respect theirs

Rules governing treaties:
• Traditionally customary
• Now codified in Vienna Convention on the Law of Treaties (in force since 1980) – only 74 signatories as of 1995

Custom

Definition:
Longstanding rules & practices or practices which are generally accepted by intl community

Customary law is universally applicable. With few exceptions, it is binding upon all states.

Consent is tacit

Customary rules are constantly changing

Establishing the existence of a customary law – must show two elements: one behavioural (state practice/usus) and one psychological (opinio juris)

State Practice (usus)

Practice must be ‘sufficiently' general:
• engaged in/observed by sufficient number of states—unanimity not required
• what is "sufficient" depends on circumstances of case
• no set threshold for practice, but practices of some states may be more relevant than others (subject area, power, geography)
• consider how often states have a chance to act in accordance/ against the rule
• look to responses of states to unilateral action

Practice must be uniform & consistent

Duration of practice:
• no particular duration is required

Opinio Juris

Practice must be accepted as law by the international community—states must believe their conduct is legally required

2 approaches:

Presumptive Approach:
• inferred from state practice unless evidence establishes contrary
• party seeking to deny custom bears burden of proof
• appropriate where issue is application of rule, not its existence

Rigorous Approach:
• requires clear evidence of psychological element
• required where existence of rule is contested or new opinio juris is alleged
• required when there is a failure of state(s) to evidence intention of parties to reject the rule

Sources of evidence:
• official pronouncements

Exceptions to Universal Character of Custom

Note: these exceptions do not apply to jus cogens.

Contracting Out

Persistent Objector

Local/Special Custom
Custom in Transition:
• where state(s) engages in new practice inconsistent with prior customary rule, it may gradually undermine the universal character of the old rule & may ultimately replace it
• permitted in the case of jus cogens only if it is replaced by a new jus cogens
• proof of change is problematic

General Exemption:
• A state allowed by the international community to deviate from a customary practice

Both treaties/conventions and custom have consensual underpinnings

• Some scholars argue that certain IL norms are non-consensual, viz. "general principles of law" and "jus cogens." – non-consensual in the sense that all are bound by their dictates

There is little agreement, however, about the nature of "general principles"

General Principles of Law

Definition:
General principles of law common to the community of states

Common Sources
• domestic procedural laws of states (but not their substantive laws)

• Principles of law (as distinct from detailed rules) may thus be borrowed if they are common to various legal systems & applied to fill the gaps in international law

3 general approaches:

• general principles are basic rules of legal logic that the ICJ may use to decide cases - i.e. the latter-in-time rule or the lex specialis rule

• general principles include substantive legal norms common to most legal systems in the world - i.e. liability for ultra-hazardous activity or basic norms of human rights

• general principles derive from natural law and are discoverable through reason

Emphasis is on procedural principles:
• res judicata (parties bound by judgement)
• judicial independence
• jurisdictional principles
• equitable principles
• secondary obligation to make reparations for breach

Examples of General Principles
• state must consent before being bound to international agreements
• states must be treated equally regardless of their size or strength
• awards/judgments of int'l tribunals to be respected as final
• one state will not interfere in domestic jurisdiction of another

Problems:
• derogates from consensual basis of IL
• risk of chauvinism & selectivity

jus cogens

2nd type of ‘non-consensual' norm: jus cogens - that is, peremptory norms from which no derogation is permitted

• closely related to natural law
• very controversial – little agreement about which norms qualify as jus cogens – candidates include prohibitions on force/aggression, slavery, genocide, and apartheid

A version of the jus cogens doctrine was accepted in the Vienna Convention on the Law of Treaties. Article 53 provides:

"A treaty is void if, at the time of its conclusion, it conflicts with a peremptory norm of international law. For the purposes of the present Convention, a peremptory norm of general international law is a norm accepted and recognized by the international community of States as a whole as a norm from which no derogation is permitted and which can be modified only by a subsequent norm of general international law having the same character."

• analogous to the rule of contract law that contract is void if contrary to public policy
• idea that there can be non-consensual norms of international law is very contentious
• thus, Vienna Convention permits the view that jus cogens is consensual – refers to peremptory norms as norms "accepted and recognized by the international community of states as a whole."
• but most discussions of jus cogens view it as non-consensual – the Convention does not permit states to derogate from jus cogens by means of a treaty & states may not opt out of jus cogens through persistent objection

Conflict with Jus Cogens:
• high burden
• controversial because of ill-defined content
• void by operation of law
• in all cases, the treaty is void ab initio—general obligation arises to return parties to status quo ante where possible
• where treaty is rendered voidable, aggrieved state may lose option if, aware of the facts, it acquiesces in the continuation in force of the treaty
• where treaty is rendered voidable, whole treaty goes unless ground of invalidity relates only to specific provisions which can be severed without injustice or absurdity
• where treaty is rendered void by operation of law, whole treaty goes

Other Sources

Article 38(1)(d) lists material sources, which are used to furnish evidence of other true sources of law.

Court Decisions:
• note no stare decisis – no ‘high court'/sovereign

Scholarly Writings:
• credentials of authors are important

Lex Ferenda – soft law (non-binding sources of law, or law in formation):
• UNGA resolutions & declarations
• SC decisions
• codes of conduct
• ILC/UN organ reports

lex ferenda may crystallise into lex lata (legally enforceable/binding rights & duties) through practice

Equity:
• concept of justice
• transcendental notion of justice
• rooted in natural law
• difficult to establish

The Hierarchy of the sources

Obligations erga omnes and international crimes

erga omnes:
Definition: norms of international law whose violation are deemed to be an offence not only against the state directly effected by the breach, but against all members of the international community' (Akehurst: 59)
• closely related to jus cogens

International crimes not the same – consists of a breach of an international obligation so serious as to constitute a treat to the ‘fundamental interests of the international community' (ILC Draft Articles on State Responsibility, Art.19(2))
• all international crimes therefore violations of erga omnes obligations, but violations of erga omnes obligations not necessarily international crimes