customary law and other sources Flashcards
constituent elements of customary law
state practice and sense of legal obligation (opinio iuris) that this conduct is allowed or required.
state practice
- conduct of all organs attributable: national laws, executive acts, national court decisions
- dealing with inter-state fact or concern
- not universal: widespread and representative
- constant and uniform
- depends particularly on those whose interest are specifically affected
- regional or bilateral customary law is possible
persistent objector
a state which wants to exempt itself from an emerging customary law by clearly expressing its opposition and maintaining it. It cannot prevent emergence but can prevent being bound by it (Norwegian Fisheries Case)
required duration for customary law
can be short if issues are not yet settled: Truman Declaration 1946, legal status of outer space after Sputnik 1957
extensive and uniform: North Sea Continental Self Cases
opinio iuris
it is accepted as law, and subjects engage or refrain from conduct because they consider it international law requires this. It is difficult to prove: it is rarely declared, can manifest in practice (laws, court rulings) or implicitly (by countermeasures).
It is difficult to prove when it is an omission (Lotus Case)
legal effect in domestic system
depends on the constitution of the respective system: B-VG recognises as part of Austrian law, so courts must apply it if there are no specific rules applicable
general principles of law
It encompasses the principles common to the main legal system of all states. It is used to fill the gaps, formally on same rank with treaties and customary law, but they are usually subsidiaries because of the lex specialis rule.
examples of general principles
- prohibition venire contra factum proprium (estoppel)
- res iudicata
- lis pendens
- duty to pay compensation
- prohibition of unjust enrichment
- duty to pay default interest
- limitation of claims
- reparation
- prohibition of abuse of rights
unilateral acts
they are actions or declarations by a single subject, they can create legal effects if there is an intention that they should create, preserve, change or terminate rights and obligation under international law. The basis for these legal effects are the principles of good faith and reciprocity.
independent unilateral acts
It creates legal rights and obliagtion without requiring acceptance by other parites, eg. promise, waiver, protest and recognition of facts and legal claims. It is decisive wheter the acting state had legal intention, which can either be explicitly expressed orm inferred from circumstances accompanying act or statement.
dependent unilateral acts
they are connected to treaties, eg. expressing consent to be bound, reservations, acts of termination or contestation of validity or submission to dispute settlement mechanisms.
forms of unilateral acts
subject to flexible formal requirements, but usually take the from of diplomatic note, note verbale or the memorandum (aide mémoire), but they can also be oral declarations.
judicial decisions
mentioned in Art. 38 as subsidiary means for identifying and interpreting rules of law. they are only binding to the parties in dispute, and most rules of procedures explicitly exclude the precendential value of stare decisis, but still they enjoy considerable authority and this leads to de facto precedent.
scholarly writings
also used as a subsidiary mean to interpret international law, courts and tribunals often cite the work of the
- International Law Commission (ILC)
- Institute de Droit International (IDI)
- International Law Association (ILA)
