Summary International Law
HC1 – Structure and Sources of International
Law
The changing structure of IL
- Peace of Westphalia created a decentralized system of sovereign
States
o International law reflects the society to which it applies.
o It starts with peace of Westphalia (1648): Treaty of Munster +
Osnabrück
o The idea was to reduce the powers transnational forces like
empire and religion
- Westphalia = Decentralized system, but emphasis on the
sovereignty of states
o Decentralized = there is no 1 ruler/ legislator ⇒ Every state
himself is responsible, only customary law
o Territorial sovereignty: other states should not intervene
within other states' domestic affairs. (There are some
exceptions).
o Westphalia was originally conceived for order for war-torn
continental Europe, but it spread to the rest of the world
- Main features:
a. Legal equality of States: All states were legally equals before
international law
b. Territorial sovereignty: The central idea is that these entities would
enjoy full territorial sovereignty
c. Non-intervention: A consequence of this principle is the non-
intervention in internal affaires of other, third states
d. State consent as the basis of legal obligation: No state will be
subject to an international rule if it had not consented to this rule ⇒
state consent would be the base for legal international obligations.
- International law was natural > natural because of what is good,
moral, fair
Classical IL reflected that structure
- Why did it reflect the structure? States were the makers and
addressees of the international law (law makers and subjects)
- International system
, o Used to only have 1 actor > the State (it only obliged states
that had consented)
o There is no central government
No parliament: Informal lawmaking process, scarce legal
rules, no hierarchy of norm
No judiciary: Self-help, often by military means (States
resolve their disputes by self-help (you attack, I attack
back))
- IL reflects the structure of the international system > IL used to
govern the relations between States
The modern IL system
But then they went from natural law to positive
law. ⇒ Positive law requires state consent.
- State is the main central actor
- Also new actors have emerged &
revolve around it, since approximately
end WO1
- Rights and obligations:
o Individuals can be held responsible
for crimes under IL (Neurenberg-Tokio)
o Transnational cooperations
o NGOs: participate in law making conference
o International organizations
Modern IL reflects the new structure of the new IL system
- New subjects of IL
- Hierarchy of legal rules
- Expansion of areas of regulations
o Coexistence: IL that has been forged to ensure that states
can co-exist
Establish boundaries
o Cooperation: Ex. Environmental law > all states have to
participate to ensure rights
Creation of institutional methods of enforcement Court of Justice s
Sources of IL
Art. 38 ICJ Statute
Primary sources – law creating
Sources that are binding
a. Treaties: Binding on parties of the treaties (consent required)
b. International customs: Binding on all. Legislation from general
practice
, c. Principles of law: Applicable to all. General principles of law
recognized by the world community
Secondary sources – law identifying
- Looking for international law, that can lead to identifying legislation
such as §a-c
- How does a treaty need to be interpreted
- Which principles are general
- Decision/analyses of the courts
No hierarchy of sources
- Sources are autonomous
o Simultaneous application > rules can be applied at the same
time
o Obligations of dual nature can be of great importance: If both
laws offer the same thing
- Conflicts of laws are settled in accordance with 2 legal principles
o Treaties, general principles and customs all have the same
value.
a. Lex posterior derogat legi priori
b. Lex specialis derogat legi generali
Hierarchy of rules
Art. 103 UN Charter: Obligations under UNC prevail over other
international obligations
Jus cogens
- Peremptory norms of international law from which no derogation is
possible
- Art. 53 and 64 VCLT: Ex. the prohibitions of aggression, crimes
against humanity, racial discrimination, torture, and slavery
- Main legal effects > rules contrary to them are null and void
Erga omnes: Genocide is erga omnes > all states have interest because of
the nature of the norm > all states can bring before the ICJ
Customary law; difficult topic
Custom is an informal (and imprecise) process of law-creation
Political implications of some issues :ex. whether UNGA resolutions
can create customs
Many of the tricky issues have not been addressed by courts
Difficult to find materials > many States don’t publish a digest of
their practice
The elements of custom
North Sea Continental Shelf cases
, - ‘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’.
1. Objective element – State practice
= General practice: it must be sufficiently widespread and
representative + consistent (Conclusion 8)
2. Subjective element – opinion juris
= Accepted as law
1. The objective element
Types of acts that constitute as practice
- Verbal & physical acts: diplomatic statements, official manuals,
instructions to armed forces, legislation
- VW: public
o Acts don’t count if they aren’t public (ex. confidential opinions
of legal advisers)
- Omission can count as a form of practice
The density of the practice
a. Uniform: asylum case: different states must not have engaged in
substantially different conduct
b. Extensive: There is no requirement of a precise number/percentage
of states
c. Representative: NSCS: must include states whose interests are
specially affected
d. Persistent objector wouldn’t be bound by the rule
2. The subjective element = psychological element
= A belief on the generality of states that the practice corresponds to a
legal obligation is sufficient to prove the existence of a rule
- Acts of comity cannot give rise to a customary obligation: Ex. Rolling
out the red carpet
Relationship between conventional law and customary
law
- Treaties may codify customary law
- The conclusion of a treaty may lead to a practice accepted as law
that becomes customary law
- Nicaragua case: custom doesn’t cease to bind States, even if the
states become parties to a treaty
HC1 – Structure and Sources of International
Law
The changing structure of IL
- Peace of Westphalia created a decentralized system of sovereign
States
o International law reflects the society to which it applies.
o It starts with peace of Westphalia (1648): Treaty of Munster +
Osnabrück
o The idea was to reduce the powers transnational forces like
empire and religion
- Westphalia = Decentralized system, but emphasis on the
sovereignty of states
o Decentralized = there is no 1 ruler/ legislator ⇒ Every state
himself is responsible, only customary law
o Territorial sovereignty: other states should not intervene
within other states' domestic affairs. (There are some
exceptions).
o Westphalia was originally conceived for order for war-torn
continental Europe, but it spread to the rest of the world
- Main features:
a. Legal equality of States: All states were legally equals before
international law
b. Territorial sovereignty: The central idea is that these entities would
enjoy full territorial sovereignty
c. Non-intervention: A consequence of this principle is the non-
intervention in internal affaires of other, third states
d. State consent as the basis of legal obligation: No state will be
subject to an international rule if it had not consented to this rule ⇒
state consent would be the base for legal international obligations.
- International law was natural > natural because of what is good,
moral, fair
Classical IL reflected that structure
- Why did it reflect the structure? States were the makers and
addressees of the international law (law makers and subjects)
- International system
, o Used to only have 1 actor > the State (it only obliged states
that had consented)
o There is no central government
No parliament: Informal lawmaking process, scarce legal
rules, no hierarchy of norm
No judiciary: Self-help, often by military means (States
resolve their disputes by self-help (you attack, I attack
back))
- IL reflects the structure of the international system > IL used to
govern the relations between States
The modern IL system
But then they went from natural law to positive
law. ⇒ Positive law requires state consent.
- State is the main central actor
- Also new actors have emerged &
revolve around it, since approximately
end WO1
- Rights and obligations:
o Individuals can be held responsible
for crimes under IL (Neurenberg-Tokio)
o Transnational cooperations
o NGOs: participate in law making conference
o International organizations
Modern IL reflects the new structure of the new IL system
- New subjects of IL
- Hierarchy of legal rules
- Expansion of areas of regulations
o Coexistence: IL that has been forged to ensure that states
can co-exist
Establish boundaries
o Cooperation: Ex. Environmental law > all states have to
participate to ensure rights
Creation of institutional methods of enforcement Court of Justice s
Sources of IL
Art. 38 ICJ Statute
Primary sources – law creating
Sources that are binding
a. Treaties: Binding on parties of the treaties (consent required)
b. International customs: Binding on all. Legislation from general
practice
, c. Principles of law: Applicable to all. General principles of law
recognized by the world community
Secondary sources – law identifying
- Looking for international law, that can lead to identifying legislation
such as §a-c
- How does a treaty need to be interpreted
- Which principles are general
- Decision/analyses of the courts
No hierarchy of sources
- Sources are autonomous
o Simultaneous application > rules can be applied at the same
time
o Obligations of dual nature can be of great importance: If both
laws offer the same thing
- Conflicts of laws are settled in accordance with 2 legal principles
o Treaties, general principles and customs all have the same
value.
a. Lex posterior derogat legi priori
b. Lex specialis derogat legi generali
Hierarchy of rules
Art. 103 UN Charter: Obligations under UNC prevail over other
international obligations
Jus cogens
- Peremptory norms of international law from which no derogation is
possible
- Art. 53 and 64 VCLT: Ex. the prohibitions of aggression, crimes
against humanity, racial discrimination, torture, and slavery
- Main legal effects > rules contrary to them are null and void
Erga omnes: Genocide is erga omnes > all states have interest because of
the nature of the norm > all states can bring before the ICJ
Customary law; difficult topic
Custom is an informal (and imprecise) process of law-creation
Political implications of some issues :ex. whether UNGA resolutions
can create customs
Many of the tricky issues have not been addressed by courts
Difficult to find materials > many States don’t publish a digest of
their practice
The elements of custom
North Sea Continental Shelf cases
, - ‘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’.
1. Objective element – State practice
= General practice: it must be sufficiently widespread and
representative + consistent (Conclusion 8)
2. Subjective element – opinion juris
= Accepted as law
1. The objective element
Types of acts that constitute as practice
- Verbal & physical acts: diplomatic statements, official manuals,
instructions to armed forces, legislation
- VW: public
o Acts don’t count if they aren’t public (ex. confidential opinions
of legal advisers)
- Omission can count as a form of practice
The density of the practice
a. Uniform: asylum case: different states must not have engaged in
substantially different conduct
b. Extensive: There is no requirement of a precise number/percentage
of states
c. Representative: NSCS: must include states whose interests are
specially affected
d. Persistent objector wouldn’t be bound by the rule
2. The subjective element = psychological element
= A belief on the generality of states that the practice corresponds to a
legal obligation is sufficient to prove the existence of a rule
- Acts of comity cannot give rise to a customary obligation: Ex. Rolling
out the red carpet
Relationship between conventional law and customary
law
- Treaties may codify customary law
- The conclusion of a treaty may lead to a practice accepted as law
that becomes customary law
- Nicaragua case: custom doesn’t cease to bind States, even if the
states become parties to a treaty
