Disclaimer: This essay has been written by a law student and not by our expert law writers. View examples of our professional work here.

Any opinions, findings, conclusions, or recommendations expressed in this material are those of the authors and do not reflect the views of LawTeacher.net. You should not treat any information in this essay as being authoritative.

Options for a State to Avoid Role of International Customary Law

Info: 2121 words (8 pages) Law Essay
Published: 27th Nov 2020

Reference this

In this essay I will examine the options open to a state that wishes to avoid being bound by a rule of customary international law in the event that this is possible. According to the doctrine, once a rule of customary international law has been established and is binding on a state (we will see under what terms), that state cannot be unilaterally exempted from the obligations imposed by such.

Firstly, to understand this matter, I must explain that international customary law consists of rules that come from "a general practice accepted as law" and that exist independently of conventional law.[1] According to Article 38 of the International Court of Justice Statute, customary international law and general principles of law are two sources of international law.[2] Customary international law is binding since states have recognized it as a source of international law, as well as treaties and, as such, are binding. In order to determine if a certain practice can be part of a binding international custom, it is important to determine the duration, coherence, repetition and generality of said particular type by the different states.The ICJ has demanded that the practices amount to "constant and uniform use" or "extensive and practically uniform" in order to be considered binding. In addition, another element that converts a mere use into a binding custom is that the practice must be accepted as opinio juris sive necessitatis (Latin: "opinion that an act is necessary by rule of law")[3] Now, to whom does this right bind and to what extent?

In principle when a practice becomes custom, all states of the international community would be bound by that custom, whether they have given their express consent or not. However, a specific practice could be restricted to certain states. Once there is enough practice along with opinio juris, a new rule of habit appears. Subject only to what would be known as the "persistent objector" principle, which means that this new rule binds all states. The persistent objector principle allows a State that has persistently rejected a new rule even before it emerged as such, to avoid its application.[4] In other words, a persistent objector is a sovereign state that since it has consistently and clearly opposed a norm of customary international law since the emergence of the norm, it will be considered that it may not be obliged to comply with it. This concept is exemplified by the positivist doctrine that says that a state can only be subject to rules to which it has given its consent.[5]

There are several cases where we can see this applied. Those can be used as guide in subsequent similar circumstances. I am now going to develop those examples:

  1. Fisheries case: A chamber of the International Court of Justice held in the Gulf of Maine case that where the practice demonstrates “that each specific case is different from all the others. This allows the possibility of those conditions arising which are necessary for the building of principles and rules of customary law”[6].
  2. Colombian-Peruvian asylum case: “The facts told to the Court disclose so much uncertainty, contradiction, fluctuation and discrepancy in the exercise of diplomatic asylum; that it is not possible to distinguish in all this any constant and uniform usage in relation with the alleged rule of unilateral and definitive qualification of the offence”[7].
  3. Case concerning the interpretation of the air transport services agreement between the United States of America and Italy, signed atrome on 6 February 1948: “It is correct that only a constant practice, observed in fact and without mutation can form a rule of customary international law”[8].

When inconsistency leads to breaches of a rule, it does not necessarily keep a general practice from its deployment. This is so when the State in case denies the violation or works in favour of the rule. As the International Court of Justice has observed: instances of State conduct inconsistent with a given rule should generally have been treated as breaches of that rule, not as signals of the legitimacy of a new rule. If a State acts in a way prima facie incompatible with a recognized rule, but supports its conduct by appealing to exceptions found within the rule itself, then whether or not the State’s conduct is in fact justiciable on that basis, the significance of that attitude is to confirm rather than to weaken the rule.[9]

Therefore, we could conclude for now that there are different aspects that address this problem. We can then say that on the one hand if a state or nation does not wish to be bound by a rule of customary international law, it could theoretically argue that it will not follow such rule[10]. And reiterating this constantly it               would not be bound by that rule.[11]

However, on the other hand, there is the peremptory norm, also called jus cogens or ius cogens, which consists of an international principle accepted by the different states by which the norm in question could not be repealed at least unilaterally.[12]  This expression literally means compulsory common law, imposed law or necessary law, the ius cogens was defined for the first time in the Vienna Convention on the Law of Treaties of May 23, 1969, specifically defining it in its article 53.[13]

The problem with this principle is that it is not possible to determine which standards are exactly those that are addressed or how a norm can be covered by jus cogens. They are considered to be fundamental rules for all states, rules that everyone understands as strictly necessary, such as the rules regarding against torture, genocide, slavery etc.[14]In addition, this is why if states, or organizations violate this principle, it would be impossible for them to claim any circumstance that would protect them, such as extreme need or force majeure. Being fundamental principles there is no way not to be bound by them[15], the only open possibility for this is provided by the aforementioned article 53 of the vienna convention, which states that considering that no agreement is accepted contrary to these fundamental rules, these could only be modified by a subsequent rule of law general international that has the same character.[16]

 Finally, to conclude with this topic, I will take a brief review of what we have seen so far. Based on what has been studied, it could be understood that there is the possibility for a state of not being bound by a rule of customary international law, in the first place, because based on previous cases this has been and therefore, it could always be possible and when performed following certain terms, we have observed based on the persistent objector principle. However, in an obvious way and based on jus cogens this will never be possible if what we are talking about are fundamental principles since these are protected and only in a remote way would this possible option be seen


  1. https://web.archive.org/web/20081226020443/http://www.law.berkeley.edu/library/classes/iflr/customary.html
  2. https://www.icj-cij.org/en/statute
  3. https://www.icj-cij.org/en/case/67
  4. https://legal.un.org/avl/pdf/ls/greenwood_outline.pdf
  5. https://www.icj-cij.org/files/case-related/7/007-19501120-JUD-01-00-EN.pdf
  6. https://legal.un.org/riaa/cases/vol_XVI/75-108.pdf
  7. https://www.icj-cij.org/files/case-related/70/070-19860627-JUD-01-00-EN.pdf
  8. https://www.britannica.com/topic/international-law/Custom
  9. https://www.icrc.org/en/war-and-law/treaties-customary-law/customary-law
  10. https://languages.oup.com/
  11.  M. Cherif Bassiouni. (Autumn 1996) "International Crimes: 'Jus Cogens' and 'Obligatio Erga Omnes'." Law and Contemporary Problems. Vol. 59, No. 4, Pg. 68.
  12. https://www.oxfordbibliographies.com/view/document/obo-9780199796953/obo-9780199796953-0124.xml
  13. https://guiasjuridicas.wolterskluwer.es/Content/Documento.aspx?params=H4sIAAAAAAAEAMtMSbF1jTAAAUNjAzMDtbLUouLM_DxbIwMDCwNzAwuQQGZapUt-ckhlQaptWmJOcSoAXzignzUAAAA=WKE

[1] See Evidence of State practice archived at the Wayback Machine, 26 Dec. 2008

[2] International court of justice, Article 38

[3]International committee of the red cross. Treaties and customary law, customary law

[4] Sources of international law: An introduction by professor Christopher Greenwood

[5]Green, James A. (2016). The Persistent Objector Rule in International Law. Oxford University Press.

[6] Delimitation of the Maritime Boundary in the Gulf of Maine Area, 25 Nov. 1981 (No. 67), ICJ, p. 131

[7] Asylum Case (Colombia/Perú), 20 Nov 1950 (No. 7), ICJ, p. 277

[8] Interpretation of the air transport services agreement between the United States of America and Italy, Advisory Opinion, 17 July 1965, United Nations, Reports of International Arbitral Awards (UNRIAA), vol. XVI (Sales No. E/F.69.V.1), pp. 75–108, at p. 100

[9] Nicaragua vs United States of America, Advisory Opinion, 27 June 1986, United Nations, Reports of  Judgments. Advisory opinions and Orders , at p. 88

[10] See Fisheries Case (UK v. Norway) [1951] ICJ Rep 116. But see also supra note 19.

[11] See Arnett, ‘Death at an Early Age: International Law Arguments Against the Death Penalty for Juveniles’, 57 U Cincinnati L Rev (1988) 245, at 260 n. 113.

[12] "Jus cogens | Definition of jus cogens in English by Oxford Dictionaries"

[13]Guías jurídicas | Ius cogens | concepto

[14]"International Crimes: 'Jus Cogens' and 'Obligatio Erga Omnes'." Law and Contemporary Problems. M. Cherif Bassiouni.Vol. 59, No. 4, Pg. 68. (Autumn 1996)

[15] Jus cogens | Anne Lagerwall. Oxford University Press. 7 Nov 2017

[16]  Guías jurídicas | Ius cogens | concepto

Cite This Work

To export a reference to this article please select a referencing stye below:

Reference Copied to Clipboard.
Reference Copied to Clipboard.
Reference Copied to Clipboard.
Reference Copied to Clipboard.
Reference Copied to Clipboard.
Reference Copied to Clipboard.
Reference Copied to Clipboard.

Related Services

View all

DMCA / Removal Request

If you are the original writer of this essay and no longer wish to have your work published on LawTeacher.net then please: