Costumary international law - unit 3 Flashcards
Customary international law
(1)Makes
(2)Changes
(3)Nullifies
unwritten international law
- Ambiguous
- More disputable
- More difficult to locate
Where do you find it?
- General proceedings
and beliefs of states
( and/or international
organisations )
=> e.g. law regarding the
immunity of states or high
level officials
Relationship between Treaty law and Customary international law:
> Exist simultaneously
Treaty law:
- Could codify existing customary
international law - Could initiate crystallisation of
customary international law - A treaty could develop customary
international law ( difficult in
practice )
opinio jurio ( sive necessitatis )
= an opinion of law ( and necessity )
Elements of Customary international law: - general practice
“words and actions of states”
Practices can come from:
* state organs
* departments
* individuals
E.g.
* domestic legislation or
regulations
* domestic court judgements
* records between ministries
* comments made during
international discussion (e.g.
UN assembly)
Needs to be:
* extensive enough
* representative
* consistent
=> does not need to be universal
=> the amount of the 3 factors
depends on the expected
frequency
Normally formed in words however can be actions:
operational conduct on the ground
= physical actions by a state
( e.g. military activities -> US Freedom of Navigation Program (FON) of 1979 )
A nonspecific period of time is
needed to become customary.
=> The practice does not need
to be fully consistent
(See Nicaragua v. US)
Elements of Customary international law: opinio juris
“out of sense of legal obligation”
To understand the existing general
practice.
Convictions of state that a certain
practice:
* is required
* needs to be prohibited
* should be allowed
=> States often do not clarify the
reasons for their practices
What does opinio juris do?
* To establish if it is customary
law or only formalities
* Helps distinguish different
types of general practice
=> However must be analysed
separately from general practice
Challenges of customary int. law:
- Evidence of the existence is hard to find
- Approx. 200 states with numerous
branches operated by individuals are
involved in the creation
=> Can be difficult to manage - States can only object/exempt before
the crystallisation of the customary
international law
Persistent objectors
= states that could be released from the application of
the customary international law
Objection must be:
* clear
* persistent throughout the formation
E.g. France, United Kingdom and United States are presistent objectors
(According to a study by the International Committee of the Red Cross.)
Particular Customary int. law:
- Binds only certain states
(e.g. states from the same region; other ties) - General practice and opinio juris is
necessary as well
=> E.g. Portugal v. India
The right of Passage over Indian Territory
(Judgement of the ICJ 1960)
Observations:
- Some states publish their practices
- Thorough examination / assessment
necessary to determine the existence
(e.g. Germany v. Italy - State Immunity
Judgement of the ICJ 2012)
⚠However only limitedly possible
respectively almost impossible
Nicaragua v. United States Judgement of 1986 (ICJ)
Customary international law regarding:
Non-use of force and non-intervention - US’s alleged breach
1. UN Charter and OAS were taken into consideration
2. General practice and opinio iuris are existent in both states
3. Validity was recognised in numerous situations
=> Therefore it’s a valid customary international law
* It is not expected that states continuously confirm to
customary international law
* If a state justifies their actions using the content of the
customary law -> the rule is reinforced
OAS = Organisation of American States
Identification of customary law 2018
(draft by the International Law Commission )
- Establishes the formalities regarding the
development and form of customary
international law
e.g. - Assessments
- Requirements
- Different forms
- Regards to other sources
