The Impact of Audit Coverage Ratio on Tax Compliance: A Systematic Mapping of Global Evidence

Abstract

This systematic literature review deconstructs the complex relationship between Audit Coverage Ratios (ACR) and tax compliance by synthesizing global evidence from 27 empirical and theoretical studies (2015–2025). The findings demonstrate that the classical "deterrence model" is insufficient for the modern fiscal landscape, as audit effectiveness is fundamentally non-linear and context-dependent. In emerging economies, increasing the ACR serves as a necessary baseline constraint; however, in low-trust or high-corruption jurisdictions, enforcement yields diminishing returns as lack of state legitimacy neutralizes moral obligation. The study identifies a "Dimensional Trap" among SMEs, where size-dependent enforcement incentivizes strategic stagnation to evade detection. Theoretically, this review supports a migration from the Allingham-Sandmo model toward the Slippery Slope Framework, while introducing "automated compliance" via digital architectures like e-invoicing. Policy implications suggest a shift from random to risk-based audits and the adoption of hybrid strategies that balance credible threats with procedural fairness. Ultimately, sustainable revenue mobilization requires tax authorities to sharpen enforcement with data while softening it with legitimacy to prevent "crowding out" intrinsic tax morale. Future research should address the long-term impact of AI-driven algorithmic enforcement on taxpayer trust.