International Criminal Accountability for Atrocity Crimes in Nigeria: Gaps, Obligations, and a Domestic Implementation Framework

Nigeria has been the theatre of potentially grave international crimes, including alleged crimes against humanity and war crimes in the context of the North East insurgency and intercommunal violence, yet domestic accountability mechanisms have produced minimal prosecutorial outcomes. The International Criminal Court's decade-long preliminary examination of the Nigeria situation, concluded without formal investigation in 2021, revealed significant accountability gaps in the domestic legal framework. This doctoral research develops an original framework for domestic implementation of international criminal accountability obligations in Nigeria, drawing on comparative state implementation experience from Uganda, Democratic Republic of Congo, and Colombia. A multi-method legal research methodology is employed, combining doctrinal analysis of Nigeria's Rome Statute obligations, the Terrorism Prevention Act 2022, and military justice legislation with empirical field research in Borno State and Plateau State communities affected by atrocity crimes. Elite interviews were conducted with prosecutors at the Attorney General's office, military courts, and international criminal law scholars. Secondary sources include ICC jurisprudence, Special Court experience literature, and complementarity scholarship from 2018 to 2024. The research makes three original contributions: an analytical mapping of domestic legal capacity gaps relative to ICC complementarity standards; an original jurisdictional design for a Hybrid Criminal Tribunal for Nigeria; and a normative theory of victim-centred accountability applicable to Nigeria's plural conflict context. Keywords: international criminal law, accountability, ICC, atrocity crimes, Nigeria.