Public International Law
State: entities possessing a territory, a population, a government, and the capacity to engage
in diplomatic or foreign relations → State is a subject of international law
Subjects of international law: State, International Organizations (e.g. UN, OECD, WTO)
and individuals (i.e. can be directly responsible for crimes against humanity or war crimes
and may be entitled to international human rights guarantees)
Other entities → objects of international law
● International law: body of law that governs relations between States and other entities
having an international personality
I. Nature of the International Legal System
● National law: concerns legal relationships of individuals with each other and the State
within this legal system. It is promulgated by a superior legal authority, recognized as
competent by the society to whom the law is addressed, and having both the authority
and competence to make and enforce the legal rules.
● International law: no established central institutions, no strong enforcement
machinery (i.e. no international police), concerned with rights and duties of the States
themselves
○ Scope of IL is not determined a priori. It covers topics that are regarded as
necessary for legal regulation at the international level
○ IL operates between equal and sovereign actors → no legal superior
○ IL is based on consensus between the subjects of international law
, International Law is concerned with rights and duties of States or IO. IL is less
structured than domestic law, since in the domestic law you only have one lawmaker,
whereas in IL, you have several States.
Sanctions are international law enforcements.
II. Sources of International Law (art. 38 of International Court of
Justice)
All the sources are equal, except ius cogens is superior. No hierarchy of norms like in the
domestic law.
Relationship between different sources has to be established by the court on a case-by-case
basis by having recourse to lex specialis derogat legi generali ( special law prevails over
general law) or lex posterior derogat legi priori (new law is superior to the older law)
, 1. Treaties (always come up in the exam)
● Bilateral or concern many States or international organisations
● Vienna Convention first defined a treaty
● A treaty is not always called a treaty, it might be called convention, protocol,
declaration, agreement, act, etc.
Example: Clinton
Is there an obligation under IL to ratify signatory States?
● Once it enters into force parties have legally binding rights and obligations → pacta
sunt servanda (perform in good faith) → failure to perform → international
responsibility art. 26 VCLT
● Treaties do not have retroactive effect ( becomes binding only after the conclusion of
the treaty)
● Treaties do not concern parties that have not adhered to the treaty
● BUT ! Some treaties have erga omnes (towards everyone) effect
● Law of treaties: r ules that deal with entry into force, termination, interpretation,
reservations, and the relationship of treaty law to custom
○ Vienna Convention on the Law of Treaties of 1969 codified the key customary
○ VCLT is applicable upon fulfillment of 3 preconditions:
■ States must be parties to the VCLT (art. 1, art. 2 para. 1 lit. a VCLT)
■ It must be a written treaty (art. 2 para. 1 lit. a VCLT)
■ Treaty must be concluded after the VCLT entered into force (art. 4
VCLT) VCLT entered into force in 1980
○ IL rules regarding international treaties → only applies to treaties in written
form
○ Treaties can be oral, in a single or several written instruments
, ○ Content: may provide obligations or rights for one party only. Precondition is
parties must have intended to create rights or duties binding under
international law.
Steps of concluding a treaty:
1st phase: negotiations (art. 6 and 9 of Vienna Convention)
2nd phase: approval procedure on national level
Domestic and political procedure (e.g. adhérer à l’UE ou non). Signing and ratifying a treaty
are not the same ! Ratification takes place after the domestic approval !
Very important or important treaties are defined by the Constitution, but it is also a political
decision (art. 140 and 141 of Cst)
State: entities possessing a territory, a population, a government, and the capacity to engage
in diplomatic or foreign relations → State is a subject of international law
Subjects of international law: State, International Organizations (e.g. UN, OECD, WTO)
and individuals (i.e. can be directly responsible for crimes against humanity or war crimes
and may be entitled to international human rights guarantees)
Other entities → objects of international law
● International law: body of law that governs relations between States and other entities
having an international personality
I. Nature of the International Legal System
● National law: concerns legal relationships of individuals with each other and the State
within this legal system. It is promulgated by a superior legal authority, recognized as
competent by the society to whom the law is addressed, and having both the authority
and competence to make and enforce the legal rules.
● International law: no established central institutions, no strong enforcement
machinery (i.e. no international police), concerned with rights and duties of the States
themselves
○ Scope of IL is not determined a priori. It covers topics that are regarded as
necessary for legal regulation at the international level
○ IL operates between equal and sovereign actors → no legal superior
○ IL is based on consensus between the subjects of international law
, International Law is concerned with rights and duties of States or IO. IL is less
structured than domestic law, since in the domestic law you only have one lawmaker,
whereas in IL, you have several States.
Sanctions are international law enforcements.
II. Sources of International Law (art. 38 of International Court of
Justice)
All the sources are equal, except ius cogens is superior. No hierarchy of norms like in the
domestic law.
Relationship between different sources has to be established by the court on a case-by-case
basis by having recourse to lex specialis derogat legi generali ( special law prevails over
general law) or lex posterior derogat legi priori (new law is superior to the older law)
, 1. Treaties (always come up in the exam)
● Bilateral or concern many States or international organisations
● Vienna Convention first defined a treaty
● A treaty is not always called a treaty, it might be called convention, protocol,
declaration, agreement, act, etc.
Example: Clinton
Is there an obligation under IL to ratify signatory States?
● Once it enters into force parties have legally binding rights and obligations → pacta
sunt servanda (perform in good faith) → failure to perform → international
responsibility art. 26 VCLT
● Treaties do not have retroactive effect ( becomes binding only after the conclusion of
the treaty)
● Treaties do not concern parties that have not adhered to the treaty
● BUT ! Some treaties have erga omnes (towards everyone) effect
● Law of treaties: r ules that deal with entry into force, termination, interpretation,
reservations, and the relationship of treaty law to custom
○ Vienna Convention on the Law of Treaties of 1969 codified the key customary
○ VCLT is applicable upon fulfillment of 3 preconditions:
■ States must be parties to the VCLT (art. 1, art. 2 para. 1 lit. a VCLT)
■ It must be a written treaty (art. 2 para. 1 lit. a VCLT)
■ Treaty must be concluded after the VCLT entered into force (art. 4
VCLT) VCLT entered into force in 1980
○ IL rules regarding international treaties → only applies to treaties in written
form
○ Treaties can be oral, in a single or several written instruments
, ○ Content: may provide obligations or rights for one party only. Precondition is
parties must have intended to create rights or duties binding under
international law.
Steps of concluding a treaty:
1st phase: negotiations (art. 6 and 9 of Vienna Convention)
2nd phase: approval procedure on national level
Domestic and political procedure (e.g. adhérer à l’UE ou non). Signing and ratifying a treaty
are not the same ! Ratification takes place after the domestic approval !
Very important or important treaties are defined by the Constitution, but it is also a political
decision (art. 140 and 141 of Cst)
