11) Consent of how many States is required for a norm to reach the level of customary international law?

How many states must follow a certain practice in the belief that it is law, for international customary law to crystallize? We know of no credible numeric rule. “How many States are required to establish ‘general’ practice and how frequent, numerous and consistent the practice must be are questions which cannot be answered in categorical propositions, according to the scholar Oscar Schachter. “Generality, frequency, density, consistency, duration are in principle required but whether they are met in regard to a specific rule depends on the circumstances of the case." 25 Even if it is not possible to say that custom will have formed when a certain precise number of states has signed or ratified the Landmine Ban, we can draw clear conclusions about other requirements for custom, and, more encouragingly, about non-requirements.

* Oscar Schachter, International Law in Theory and Practice, p. 9 (1991).

http://www.the-monitor.org/index.php/publications/display?url=lm/1999/appendices/custom_law.html

12) The concept of persistent objector

persistent objector - юр. настойчиво возражающее государство

The doctrine of the persistent objector ("the doctrine") limits the enforceability of international laws. According to the doctrine, if a state persistently objects to the development of a customary international law, it cannot be held to that law when the custom ripens. Presently, persistent objection is a valid defense unless the customary international law attains the rare status of a peremptory norm or, as it is referred to in Latin, a jus cogens. Under existing international law, only a handful of human rights norms qualify as jus cogens,1 leaving the large majority of human rights laws susceptible to the persistent objector doctrine. This Comment argues that application of the persistent objector doctrine to customary human rights law is undertheorized and, consequently, misguided. This Comment proposes a reformulated doctrine that would be less accessible as a defense against human rights violations.

//// The history of the doctrine is rather thin. Prior to Oomingues, the doctrine had only been recognized by an international tribunal on two other occasions.21 Those two cases are Colombia v Peru (the Asylum Case)22 and United Kingdom v Norway (the Fisheries Case)23-both of which were adjudicated by the International Court of Justice ("ICJ"). It is notable that in both cases, the ICJ's recognition of the persistent objector doctrine was purely dictum and the ICJ had resolved the disputes on other grounds.24 Even more notably, neither the Asylum Case nor the Fisheries Case addressed human rights law. The Asylum case addressed whether Peru's repudiation of a treaty's asylum provision amounted to persistent objection.25 The Fisheries Case addressed whether Norway's repeated opposition to the demarcation of a fishing zone amounted to persistent objection.26 As discussed below in Part III, invoking the persistent objector doctrine in the human rights context creates a unique tension worth discussing. Neither the Asylum Case nor the Fisheries Case discussed this unique tension and, therefore, their persuasiveness as precedents is limited.

http://www.allbusiness.com/legal/international-law/884010-1.html

+ http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1653351

However, the International Court of Justice has endorsed the persistent objector rule only twice, and arguably both times in obiter dicta. Fisheries case (UK v. Nor.), 1951 + Asylum case … (http://www.asil.org/ajil/roberts.pdf )