,[Typ hier]
Sources
There is no single body able to create laws internationally binding upon everyone, nor a proper system of
courts with comprehensive and compulsory jurisdiction to interpret and extend the law. By ‘sources’ one
means those provisions operating within the legal system on a technical level, and such ultimate sources as
reason or morality are excluded, as are more functional sources such as libraries and journals.
Article 38(1) of the Statute of the International Court of Justice is widely recognised as the most authoritative
and complete statement as to the sources of international law: “The Court, whose function is to decide in
accordance with international law such disputes as are submitted to it, shall apply: (a) international
conventions, whether general or particular, establishing rules expressly recognised by the contesting states; (b)
international custom, as evidence of a general practise accepted as law; (c) the general principles of law
recognised by civilized nations; (d) subject to the provisions of Article 59, judicial decisions and the teachings of
the most highly qualified publicists of the various nations, as subsidiary means for the determination of rules of
law”.
A distinction has sometimes been made between formal and material sources. The former, it is claimed, confer
upon the rules an obligatory character, while the latter comprise the actual content of the rules.
3.1 Custom
3.1.1 Introduction
The essence of custom according to Article 38 is that it should constitute ‘evidence of a general practise
accepted as law’. Thus, it is possible to detect two basic elements in the make-up of a custom. These are the
material facts, that is, the actual behaviour of states, and the psychological or subjective belief that such
behaviour is ‘law’. As the International Court noted in the Libya/Malta case, the substance of customary law
must be ‘looked for primarily in the actual practise and opinio juris of state’.
3.1.2 The Material Fact
The basic rule as regards continuity and repetition was laid down in the Asylum case decided by the ICJ in 1950.
The Court declared that a customary rule must be ‘in accordance with a constant and uniform usage practised
by the States in question.
The ICJ emphasized its view that some degree of uniformity amongst state practise was essential before a
custom could come into existence in the Anglo-Norwegian Fisheries case.
In the North Sea Continental Shelf cases, which involved a dispute between Germany on the one hand and
Holland and Denmark on the other over the delimitation of the continental shelf, the ICJ remarked that state
practise, ‘including that of states whose interests are specifically affected’, had to be ‘both extensive and
virtually uniform in the sense of the provision invoked’. This was held to be indispensable to the formation of a
new rule of customary international law. However, the Court emphasized in the Nicaragua v. United States
case that it was not necessary that the practise in question had to be ‘in absolute rigorous conformity’ with the
purported customary rule. The court continued: “In order to deduce the existence of customary rules, the Court
deems it sufficient that the conduct of states should, in general, be consistent with such rules and that instances
of state conduct inconsistent with a given rule should generally have been treated as breaches of that rule, not
as indications of the recognition of a new rule’.
One can conclude by stating that for a custom to be accepted and recognised it must have to concurrence of
the major powers in that particular field. A regulation regarding the breadth of the territorial sea is unlikely to
be treated as law if the great maritime nations do nog agree to or acquiesce in it, no matter how many
landlocked states demand it. Other countries may propose ideas and institute pressure, but without the
concurrence of those most interested, it cannot amount to a rule of customary law. This follows from the
nature of the international system where all may participate but the views of those with greater power carry
greater weight.
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, Failures to act are in themselves just as much evidence of a state’s attitudes as are actions. They similarly
reflect the way in which a nation approaches its environment. It has been maintained that the continued habit
of not taking actions in certain situations may lead to the formation of a legal rule.
In the particular circumstances of the Lotus case the Permanent Court of International Justice, the predecessor
of the ICJ, laid down a high standard by declaring that abstention could only give rise to the recognition of a
custom if it was based on a conscious duty to abstain. In other words, states had actually to be aware that they
were acting a particular way because they were under a definite obligation not to act that way.
3.1.3 What is state practise?
It is how states behave in practise that forms the basis of customary law, but evidence of what a state does can
be obtained from numerous sources. Obvious examples include administrative acts, legislation, decisions of
domestic courts and activities on the international stage, for example treaty-making. The obvious way to find
out how countries are behaving is to read the newspapers, consult historical records, listen to what
governmental authorities are saying and peruse the many official publications.
International organisations in fact may be instrumental in the creation of customary law. For example, the
Advisory Opinion of the ICJ declaring that the United Nations possessed international personality was partly
based on the actual behaviour of the UN.
States’ municipal law may in certain circumstances form the basis of customary rules. In the Scotia case
decided by the US Supreme Court in 1871, a British ship had sunk an American vessel on the high seas. The
Court held that British navigational procedures established by an Act of Parliament formed the basis of the
relevant international custom since other states had legislated in virtually identical terms.
It should be noted that not all elements of practise are equal in their weight and the value to be given to state
conduct will depend upon its nature and provenance.
3.1.3.1 Opinio juris
Once one has established the existence of a specified usage, it becomes necessary to consider how the state
views its own behaviour. The opinio juris, or belief that a state activity is legally obligatory, is the factor which
turns the usage into a custom and renders it part of the rules of international law. The Permanent Court of
International Justice expressed this point of view when it dealt with the Locus case.
Among the various arguments adduced, the French maintained that there existed a rule of customary law to
the effect that the flag state of the accused (France) had exclusive jurisdiction in such cases and that
accordingly the national state of the victim (Turkey) was barred from trying him. To justify this, France referred
to the absence of previous criminal prosecutions by such states in similar situations and from this deduced tacit
consent in the practise which therefore became a legal custom. The Court rejected this and declared that even
if such practise of abstention form instituting criminal proceedings could be proved that, it would not amount
in custom. It held that ‘only if such abstention were based on their [the states] being conscious of duty to
abstain would it be possible to speak of an international custom.
The great problem connected with the opinio juris is that if it calls or behaviour in accordance with law, how
can new customary rules be created since that obviously requires action different from or contrary to what
until then is regarded as law? Thus, one has to treat the matter in terms of a process whereby states behave in
a certain way in the belief that such behaviour is law or is becoming law. It will then depend upon how other
states react as to whether this process of legislation is accepted or rejected.
Faced with the difficulty in practise of proving the existence of the opinio juris, increasing reference has been
made to conduct within international organisations. This is so particularly with regard to the UN. The ICJ has in
a number of cases utilised General Assembly resolutions as confirming the existence of the opinio juris
focussing on the content of the resolution or resolutions in question and the conditions of their adoption.
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