“Jus Cogens” and “Erga Omnes”
I will be speaking about Barcelona Traction, Light and Power Company case and the Nicaragua Vs. United States Of America case. jus cogens, is one of the most important concepts in international law. This concept comes from the Romans.To learn more, read the entire article Two Pillars Of International Law
This paper will deal with “Jus Cogens” and “Erga Omnes”; I will be speaking about the main features of these two extremely important concepts in Public International Law. In the second half of the paper, I will be analyzing two very important cases that were decided by the International Court Of Justice. The first case will be the Barcelona Traction, Light and Power Company case and the second one will be the Nicaragua Vs. United States Of America case.
Starting with jus cogens, this is one of the most important concepts in international law. This term is a Latin term that directly translates to “compelling law”. In simpler terms, it refers to fundamental and overriding principles of international law.Now to get down to the meat of the matter, this concept comes from the Romans who said that there are certain legal rules and regulations that cannot be contracted out as they uphold very strong fundamental values. These particular norms cannot be ignored or held to be invalid by any other separate treaty between states. In the modern day and age, most countries across the world do agree with concept of jus cogens and are willing to follow it as this helps all the countries across the globe. The two Vienna Conventions in the years 1969 and 1986 on the Law Of Treaties came up with the decision that a treaty will be held void if it conflicts with jus cogens. Art 53 of the 1969 Vienna Convention on the Law Of Treaties says that a treaty will held void if at that particular time it is in conflict with a peremptory norm of general international law. It was also held that a peremptory norm is a certain norm that is accepted and recognized by the international community of states. They also declared that these norms could only be modified by a future norm of international having the same or at least similar character. Another important Article is Article 64 of the 1986 Vienna Convention, this article stated that if a new peremptory norm of general international law emerges, all existing treaties, which are in conflict with that particular norm, will become void and are terminated. To establish a peremptory norm, the authorities have to make sure that the norm in question checks two boxes. The first box being it is a norm of international law and the second box being that it is accepted and recognized by the international community of states as a whole. The states also have to agree that no derogation is allowed and this norm can be only modified by a norm that has similar or same nature. There are two very important and common sources for jus cogens. First one being Customary International Law and the second one being certain treaty provisions and specific general principles of law. These two specific domains of law contribute to the forming of jus cogens. Now coming to a slight tricky part that involves jus cogens, I will be elaborating on the separability of treaty provisions that conflict with jus cogens. For example, if a treaty which at the time of forming is conflicting with a peremptory norm of international law then the whole treaty is held to be void and not only that specific part of the treaty. This shows that no separation of treaty provisions are permissible when it comes to jus cogens. However, there are certain exceptions that are applicable when it comes to the separation of treaty provisions if they conflict with jus cogens. The first exception being that if the provisions that are in conflict with jus cogens can be separated from the entire treaty then the treaty will be not be held void. The second exception being that if the acceptance of these provisions were not essential for any of the parties that had given their consent to the treaty. The third and final exception if the treaty was still followed by the parties that had signed it, then it would not be unjust. Now moving onto the next step, for example if a country has signed a treaty that then turns out to be void because the treaty is actually in conflict with the peremptory norms of international law. Now this country has one major legal obligations to follow concerning this treaty. The legal obligation is to try to eliminate any effects of any act performed based on the provisions that are in conflict with jus cogens. 
Now moving onto the Erga Omnes, just as jus cogens this is also an extremely important concept in the realm of Public International Law. With respect to ordinary obligations, for example: the state that has defaulted bears responsibility to any other states that had any kind of interest in that particular treaty. However, under the realm of erga omnes, there are certain determined obligations that the states have towards the international community as a whole. Erga omnes is also a Latin term that directly translates to “in relation to everyone”. It stems from the idea that a breach of an erga omnes obligation does not only the concern the state which is the victim but also all the other members of the international community. If there is a breach of an erga omnes obligation, then all the states of the international community have the right to invoke responsibility in the guilty state. Now coming onto the difference between jus cogens and erga omnes, both these concepts are opposite sides of the same coin. There is no particular difference but one line that could sum it up is a jus cogens rule produces an erga omnes obligation that countries have to comply with as a rule. Thus, an erga omnes obligation is the effect of a rule being termed being termed as jus cogens. 
Moving onto the two cases that I will be speaking about. I will be starting with the Barcelona Traction, Light and Power Company case. In terms of erga omnes, this was an extremely important case and this case actually set the ball rolling by the International Court Of Justice as they coined the term “erga omnes obligations” in this particular case. The facts of this case are extremely simple, on behalf on certain nationals who had invested in a particular Canadian company, Belgium went ahead and sued Spain. They sued Spain on the basis that they were actually responsible for acts in violation of international law that had not only caused significant injury to that particular Canadian company but also the Belgian shareholders who held shares in that company. In extremely brief terms, the ICJ held that Belgium had no legal interest in the matter thus they could not justify bringing a claim. Even though Belgian shareholders suffered in this whole case, only the company’s rights could have actually been infringed by Spain’s actions and not of the individual shareholders. The ICJ in this landmark judgment gave birth to the concept of “erga omnes obligations”. The court spoke specifically spoke about four erga omnes obligations; first one being that any acts of aggression would be outlawed, second being outlawing the act of genocide, third being protection from slavery and lastly protection from racial discrimination. In this particular judgement, the ICJ distinguished between erga omnes obligations and those obligations that a states hold with respect to other states. In paragraph 33 of the judgment, it was held that erga omnes obligations apply to all states in the international community as those acts involve the security of the states even if they aren’t directly involved in the act. They also gave a very interesting example to distinguish between the two, erga omnes obligations are compared to property rights, as they are applicable to everybody while the rights that only apply to certain states are compared to a contract that is applicable to only the parties that actually sign the contract. The court also finally held in this case that it was a general rule of international law that when an unlawful act was committed against a company, only the state of incorporation of the company could sue and since Canada had chosen not to that means no one will be able to. Now going on to diplomatic protection, this was a contention raised by Belgium that was squashed by the ICJ saying that diplomatic protection of shareholders was unsound because it would create confusion and insecurity in economic relations, as shares are “widely scattered and frequently change hands”. This was a landmark judgment as it showed the way for the future and gave the judges the direction on how to apply the concept of erga omnes to their future judgments. 
Now moving onto the next case which was also a landmark judgement concerning Public International Law. This was case was the Nicaragua Vs. United States Of America case which was under severe scrutiny as it involved one of the most powerful nations in the world. The case primarily deals with military and paramilitary activities conducted by or at least with the help of America against Nicaragua in the 3 year span between 1981 and 1984.The facts of this case are also extremely straightforward, in July 1979, the government of President Somoza was replaced by a government installed by the “Frente Sandinista de Liberacion Nacional” also known as FSLN. The United States initially was supportive of the new government but then stopped favoring the government when it found out that Nicaragua was helping guerillas by providing logistical support to them. In 1981, it was found that the American government had decided to undertake activities against Nicaragua, initially all these activities were taking place in a covert fashion but then slowly the American government took responsibility for all these actions. First speaking about the part of the judgement that deals with the concept of jus cogens. The ICJ held that Article 2(4) of the UN Charter prohibits the use of force against any other state. They also stated that this specific prohibition can be found under customary international law and is a jus cogens norm. The court also went and further said that this kind of force used by America against Nicaragua can be considered to a “grave use of force”. Since it was declared that the prohibition of usage of force was a jus cogens norm, The United States Of America had clearly violated this particular jus cogens norm and thus were clearly guilty. There were four other significant questions raised and the ICJ gave their stance on each of these questions. The first question was whether the court competent to give a decision based on CIL when there is multilateral treaty reservation. The court answered by saying that multilateral treaty reservations cannot preclude the court from relying on CIL because customary law exists independently of treaty law. The second question was to do with the relationship between treaty and customary international law. The court stated that CIL will always coexist with treaty law and they held that any areas of law governed by the two sources of law do not always overlap and the rules do not always have the same content. They also held that principles such as non-use of force, respect for independence and other such principles would always be a part of CIL despite of anything else. The third question is a very common question in the realm of International Law, this question deals with which elements are necessary to form CIL. The court answered this by saying that opinio juris and state practice will always be necessary elements to determine as to what classifies as CIL. The fourth and final question before the court was what is the status of the principle of non-intervention concerning CIL? The court started by saying that the principle of non – intervention requires that every state has a right to conduct its affairs without outside interference. The court finally held that principle of non- intervention is CIL and there can be no debate about such fact. 
Overall, in both these judgements the ICJ has done justice to not only the respective parties but also the international community as a whole. The realm of international law since has been developing for more than 100 years and is still developing. There will there never be a time when international law has been 100% developed as things in the international community keep changing.
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