Workplace Ethics, Anti-Corruption Policies, and Staff Integrity in the Nigerian Revenue Service: A Case Study of FIRS in Enugu

This study investigates the relationship between workplace ethics frameworks, anti-corruption policies, and staff integrity outcomes in the Federal Inland Revenue Service (FIRS), Enugu State office, South East Nigeria. Revenue collection agencies are particularly vulnerable to corruption, making the design and enforcement of ethics programs a critical HR management priority with direct implications for national fiscal health. A professional research design was employed, with 75 FIRS staff across revenue, compliance, and administration units responding to questionnaires and participating in key informant interviews. The Ethical Climate Theory, Trevino's Integrative Model of Ethical Decision-Making, and recent anti-corruption governance frameworks underpin the study. Findings reveal that staff in units with active ethics training, visible disciplinary enforcement, and anonymous reporting mechanisms demonstrate significantly higher self-reported integrity scores and lower incidents of facilitation payments compared to units lacking these structures. The study identifies leadership role-modelling as the single most powerful determinant of ethical behaviour at operational levels, with staff citing supervisors' conduct as more influential than written codes of conduct. Weak whistleblower protection and fear of social ostracism are identified as the primary barriers to reporting observed misconduct. Recommendations include executive ethics leadership programs, strengthening the FIRS internal anti-corruption unit, mandatory ethics refreshers every two years, and legislative enhancement of whistleblower protections. This study contributes to the literature on institutional integrity in Nigeria's revenue administration sector. Keywords: workplace ethics, anti-corruption, staff integrity, FIRS, revenue service