محمدرضا گنج خانلو

Background and Theoretical Foundations: Marine oil pollution represents one of the most severe threats to the marine environment, with long-lasting ecological, economic, and social consequences. While civil liability regimes have been extensively developed under international conventions, the realm of criminal liability—especially for both natural and legal persons—remains fragmented and inconsistently applied across jurisdictions. Theoretical underpinnings of criminal liability are rooted in the principles of international environmental law, state sovereignty, and the evolving recognition of corporate culpability under international legal frameworks. Key conventions such as the United Nations Convention on the Law of the Sea (UNCLOS), the MARPOL 73/78 Convention, and the International Convention on Oil Pollution Preparedness, Response and Co-operation (OPRC) set the stage for state responsibilities and potential penal responses to pollution incidents, yet do not explicitly create unified standards of criminal prosecution for polluters.   Methodology: This article applies a comparative and analytical legal methodology grounded in the study of international treaties, customary international law, case law, and state practice. It examines both soft law instruments and binding conventions, alongside selected national laws and prosecutions.  Findings: The research reveals significant gaps in the international legal system’s approach to criminal liability for marine oil pollution. While several instruments impose obligations on states to adopt penal measures, enforcement varies widely, and the actual prosecution of corporate actors is rare. States often rely on civil penalties or administrative sanctions. However, where domestic laws are aligned with international obligations—such as in the U.S. or the EU—criminal prosecutions have led to substantial deterrent outcomes. Furthermore, corporate criminal liability, although increasingly recognized, remains legally ambiguous in many jurisdictions, and international law does not yet fully incorporate binding norms in this regard. Conclusion: International law recognizes the seriousness of marine oil pollution but lacks a harmonized and enforceable framework for holding individuals and corporations criminally liable. To bridge this gap, a more robust international regime is needed—one that explicitly defines environmental crimes at sea, standardizes evidentiary thresholds, and fosters cooperative enforcement among flag, coastal, and port states. Enhancing international cooperation, supporting capacity building in developing states, and codifying corporate environmental responsibility are essential steps toward achieving greater accountability and marine environmental protection on a global scale. Keywords: Marine Oil Pollution, Individual Criminal Liability, Corporate Criminal Liability, International Environmental Law, MARPOL Convention,