Theorising Islamic Constitutionalism in Nigeria: Sharia, Secularism, and the Federal Architecture

This dissertation theorises Islamic constitutionalism as a viable paradigm within Nigeria's federal constitutional architecture, examining the jurisprudential, political, and sociological dimensions of Sharia's incorporation into state law across twelve northern states since 1999. The coexistence of Sharia law within a secular federal constitution represents a globally distinctive constitutional arrangement whose theoretical foundations remain insufficiently analysed in both Islamic jurisprudence and Nigerian constitutional scholarship. The study employs an interdisciplinary theoretical legal research methodology, drawing on Islamic constitutional theory, comparative federalism, and critical legal studies. Primary sources include 90 Sharia-related court judgments, constitutional texts and amendments, and interviews with 35 Islamic legal scholars, constitutional lawyers, and state government officials in Zamfara, Kano, and Kebbi states. The original contribution to knowledge is a Theory of Negotiated Islamic Constitutionalism that accounts for the dynamic interplay between federal secularism and state-level Islamic governance. Findings reveal that the current constitutional arrangement produces creative jurisdictional tensions that have stimulated productive jurisprudential innovation but also generate human rights conflicts requiring principled resolution. The dissertation proposes a constitutional Maslaha doctrine as a mechanism for resolving Sharia-secularism tensions within the federal framework. Keywords: Islamic constitutionalism, Sharia, secularism, Nigerian federalism, constitutional theory.