Lecture 5: Sources of international law

Question 1

Ex aequo et bono

Answer 1

= according to the right and good

Power for the ICJ to decide cases based on what they feel is right without reference to any rule of positive law. A small remnant of natural law, but seldom used

Question 2

What is generally considered an authoritative source of IL

Answer 2

Article 38(1) of the Statutes of the ICJ

Question 3

The rules relating to treaties are part of what

Answer 3

Customary IL, but codified in the Vienna Convention on the Law of Treaties which is viewed as the authoritative restatement/positive law of treaties

Question 4

Philosophical debate: are treaties law?

Answer 4

Strictly speaking, some argue that treaties are not sources of law as much as they are a source of obligation under the law, binding on its parties

Question 5

Pacta sunt servanda

Answer 5

= Agreements must be kept

Most important rule of customary IL, saying that treaties have to be obeyed because agreements/promises must be kept

Question 6

Who can treaties bind?

Answer 6

Parties to the treaty (although non-parties can choose to abide by the rules if it benefits them or they see the rules as part of customary IL)

Question 7

What can treaties do?

Answer 7

Pretty much anything, except authorize the violation of a peremptory norm such as genocide, piracy etc.

Question 8

Is there a distinction between “law-making” treaties and “contractual” treaties?

Answer 8

Not really, all treaties are contractual in they either make new rules and principles or create new obligations

Question 9

Who can make a treaty?

Answer 9

Treaties are written and made between states represented by people authorized to do so

Question 10

How can treaties be distinguished from other international agreements?

Answer 10

They are legally binding

Question 11

6 key components of a treaty

Answer 11

1. Preamble
2. Signatories’ names (sometimes)
3. Main body
4. Signatures/seals
5. Reservations (if possible - disagreements with certain provisions)
6. Protocols (amendments made to treaties afterwards, do not necessarily apply to all countries?

Question 12

Treaties are not binding until…

Answer 12

The parties have ratified it domestically either by the executive or the legislature (but in the meantime states are not supposed to do anything that defeats the purpose of the treaty)

Question 13

Treaties in monist vs. dualist systems

Answer 13

In monist systems, treaties do not need to be translated into municipal law - they have immediate effect once ratified and become part of domestic law

In dualist systems, domestic legislation is required to translate the treaty obligations into municipal law

Some states have a mix of the two

Question 14

3 ways that treaties can end

Answer 14

1. On its own terms (self-termination, expiry, disappearance of essential conditions)
2. By withdrawal/denunciation
3. In response to serious breach by one party (but should be a last resort)

Question 15

For a custom to become law, these 2 elements have to exist

Answer 15

1. Evidence of widespread and settled state practice (actions, domestic courts and legislatures, public statements)
2. Opinio juris: States adhere to the custom because they believe they have a legal duty to do so

Question 16

Opinio juris (and critique)

Answer 16

States adhere to a custom because they believe they have a legal duty to do so (e.g. they believe they are legally bound to do so, not because it’s nice to do)

Somewhat artificial as it implies states have a collective mind and intentionality of its own

Question 17

In what 2 ways can you avoid customary IL?

Answer 17

1. If enough countries persistently breach the law, the breach can become normalized and your new practice becomes law
2. One state can prevent being bound by an emerging rule of customary IL by acting as a persistent objector (e.g. silence is not enough, must voice objection persistently)

Question 18

When is customary law inferior?

Answer 18

For parties to a treaty, e.g. if a treaty and customary IL has different/contrasting rules, the treaty replaces the customary rules for the parties but not for non-parties

Question 19

What are the 2 views of the ‘general principles recognized by civilized nations’?

Answer 19

1. Principles found in most or all municipal law systems, but which do not exist as positive IL
   OR
2. Also includes very basic legal principles such as pacta sunt servanda (agreements must be kept)

Question 20

How can judicial decisions and writings of publicists be a source of IL?

Answer 20

It is not a source of law, but a source for determining what a law is in a given situation

Can only be used as subsidiary means, because they are usually derived from the other 3 sources of law

Question 21

Are there precedents in IL?

Answer 21

No, there are no binding precedents! Judicial decisions are only binding in that specific case for the parties involved

But ICJ has a tendency to cite itself regarding the content of customary IL

Question 22

What are the 4 main sources of IL?

Answer 22

1. Treaties
2. Customary IL
3. General principles recognized by civilized nations
4. Judicial decisions and writings of publicists

Question 23

What are 3 other, less important sources of law?

Answer 23

1. Resolutions of UNGA, although not binding
2. Studies produced by International Law Commission, even if not adopted
3. UNSC creating specific obligations (but not new law in itself)

Question 24

Ius cogens

Answer 24

Peremptory norms that all countries must obey:

1. Wars of aggression
2. Genocide/crimes against humanity/apartheid
3. Slavery/torture/execution of juvenile offenders
4. Oiracy

Question 25

Lex specialis and lex posterior

Answer 25

Principles of hierarchy in IL:

Lex specialis: The specific rule prevails over the general rule

Lex posterior: The more recent rule overrides the earlier rule

Question 26

Does customary law always prevail over treaties?

Answer 26

Treaties are assumed to be lex specialis over customary IL

But if a customary rule is peremptory, it overrides the treaty