Properly speaking, international criminal responsibility is not a new chapter of public international law, but rather the recent revival of an old chapter of the Law of Nations. In the recent past, we have seen the emergence of ad hoc international criminal tribunals that is with a limited competence, as established in their statutes. Instead, today’s International Criminal Court enjoys, within its statutory (treaty) limits, a general jurisdiction; it is thus a permanent organ of a general character, mirroring the ICJ in matters of international criminal law. It will also be in charge of the international criminal responsibility of the individuals.
In contrast with the two previous approaches, based on ‘right’, we will deal here with ‘obligations’ that are bestowed upon the individual, that is, international obligations not to commit some acts characterized as crimina iuris gentium. PIL deals with the individual by prohibiting the perpetration of such crimes. The individual is therefore construed as the passive subject within international legal relations; he must account – before municipal and international courts alike – for his misdeeds (violation of international obligations) committed against States as well as other individuals. Thus, if, from the angle of international human rights protection, responsibility involved an active personality, in this case the personality is deemed to be passive.
Aside from international “crimes” of the States whose existence remains to be carefully considered, international law contemplates the existence of certain categories of crimes committed by individuals acting either individually, or as State organs. Still, only a few of these violations are susceptible to be prosecuted and punished on the international plane while others are only prosecuted and punished by national jurisdictions.
The revolutionary developments which have punctuated this province of PIL from the second half of the Twentieth century onwards, severely stepping into one of the core elements of the State reserved domain (of criminal repression) show that the individual must also be considered as an international subject in this domain, as long as he is directly prosecuted and tried by an international judiciary mechanism.
It is indeed on the plane of international punishment of these crimes that the individual arose in international law as a bearer of international obligations, and as such as a subject of international law. Finally, it is important to note that an individual’s criminal responsibility does not affect, in any way, the eventual concomitant international responsibility of the State, on the contrary this “duality of responsibility continues to be a constant feature of international law”. Indeed, if its conduct can be attributed to a State in one way or another, then the State’s international responsibility can be engaged. Henceforth, there will be two international responsibility (the individual’s and the State’s) within the international legal order which could give rise to different types of repression and forms of sanctions.
Keywords: international criminal responsibility, international criminal law, war crimes, crimes against humanity, crime of aggression, crime of genocide, International Criminal Court, ad hoc international criminal tribunals.
 For instance, Former Yugoslavia and Rwanda
 It ought to be noted that individual’s international criminal responsibility is not in fact incurred vis-à-vis those persons who have actually suffered (or were affected) by the perpetration of his crime. Here we find again, yet with inverted roles, the same equation in the previous two perspectives, i.e. State or the International Community (injured party) and individual (defaulting party).
 See: G. Distefano, Fundamentals of Public International Law. A Sketch of the International Legal Order, Leiden, 2019, pp. 700-702.
 See: G. Balladore Pallieri, 1962, pp. 221-222; S. Romano, 1933, pp. 76-77; R. Quadri, 1968, pp. 407-408 (since the condition this famous jurist set forward – i.e. the existence of international organs endowed with the power to repress on the international plane these international crimes – has henceforth been fulfilled); A. Cassese, 2001, pp. 79-81; A. Verdross, B. Simma, 1984, §§ 430-443 (pp. 260-267);
 Application of the Convention on the Prevention and Punishment of the Crime of Genocide, 2007, § 173 (at 116). See Article 25 § 4 of the ICC Statute as well as Article 58 IR 2001, which recites: ““These articles are without prejudice to any question of the individual responsibility under international law of any person acting on behalf of a State.”
 See: G: Distefano, 2019, pp. 653-695.
 “The State, and those acting on its behalf, bear criminal responsibility for such violations of international law as by reason of their gravity, their ruthlessness, and their contempt for human life place them within the category of criminal acts as generally understood in the law of civilized countries”, Oppenheim’s International Law, 8th ed. (Sir Hersch Lauterpacht), p. 355.
"International Criminal Responsibility of the Individual: A Quantum Leap for Man’s Humanity,"
UAEU Law Journal: Vol. 2021:
85, Article 10.
Available at: https://scholarworks.uaeu.ac.ae/sharia_and_law/vol2021/iss85/10