Promotional Jus Cogens: A Critical Appraisal of Jus Cogens’ Legal Effects

Traditionally the problem of jus cogens has been conceptualised as a problem of identification of peremptory norms, taking as a starting point Articles 53 and 64 of the 1969 Vienna Convention on the Law of Treaties. These provisions in fact, while defining jus cogens and contemplating invalidity and termination as special effects affecting incompatible treaties, fail to enumerate what norms are to be considered peremptory. In recent times, however, jus cogens has been invoked and applied – as a sort of “super-law” taking precedence over all other international norms – in legal contexts other than the law of treaties with a variety of “special” or “derogatory” effects. Such an expansion calls for a refocusing of the “identification” problem surrounding jus cogens in terms of effects rather than, or solely, in terms of norms. But it seems that the effects usually ascribed to jus cogens cannot be unlimited in number and scope. This implies that a criterion is needed to determine if and to what extent a certain jus cogens’ effect is produced. It is submitted that a fully inductive approach should be taken. Jus cogens appears then in most cases to be relied upon ad abundantiam to “prove” a special effect which already fl ows either from an applicable treaty or from state practice and opinio iuris. In the remaining instances, reliance upon jus cogens seems to amount to invoking the need for the emergence of a corresponding new customary norm in the future, evidently on the assumption (whether right or wrong) that this norm does not exist yet or is not yet well-established. As a result, the key constructive meaning that can be attached to jus cogens is “promotional” – hence provisional and “deontological” – insofar as the interpreter feels that a precedent, which is assumed as reflecting a fundamental value of the international community as a whole and capable of reasonably being accepted by the generality of states, should be set in order to bring about a change in existing law