In January 2026, the United States reportedly conducted a military operation on Venezuelan territory resulting in the forcible capture and transfer of President Nicolás Maduro for criminal prosecution, without the consent of Venezuela or authorisation from the United Nations Security Council. This thesis uses that scenario as a case study to examine to what extent the forcible capture and transfer of a sitting head of state by a foreign military can constitute an act of aggression engaging individual criminal responsibility under Article 8 bis of the Rome Statute, and how the resulting international illegality interacts with the domestic legal validity of a prosecution founded upon that same conduct.
Applying a doctrinal legal method, the thesis finds that such an operation satisfies the use-of-force threshold under Article 2(4) of the UN Charter and meets the manifest violation standard under Article 8 bis(1), and that the leadership requirement, modes of liability, and mental element of the crime of aggression are capable of being satisfied on the facts. However, the jurisdictional architecture of the Rome Statute renders this responsibility unenforceable in practice, since the acting state's non-party status forecloses the Court's jurisdiction absent a Security Council referral. At the same time, domestic doctrines such as male captus bene detentus permit the resulting prosecution to proceed notwithstanding the international illegality of the capture and the violation of head-of-state immunity. The thesis concludes that this divergence between international illegality and domestic legal validity is a structural feature of the contemporary legal order, exposing the limits of the crime of aggression as a mechanism of accountability.