Tax Enforcement and Revenue Mobilisation in the Global South: Political Constraints, Fiscal Evidence, and Methodological Scrutiny

Domestic revenue mobilization (DRM) is a cornerstone of development, vital for financing public goods, fostering legitimacy, and reducing external dependence. Yet across much of the Global South, revenue performance remains below potential despite repeated reforms. Technical measures—such as administrative modernization, digital enforcement, and behavioral interventions—have expanded the toolkit and delivered gains. However, they operate within political settlements, elite bargains, and institutional legacies that shape both enforcement outcomes and reform trajectories. This dissertation integrates political economy analysis, fiscal instrument design, and methodological critique to explain and improve DRM in low-capacity states. The first three papers focus on the politics of taxation. Chapter 2 develops a framework embedding enforcement outcomes in elite power configurations. Chapter 3 applies this to Uganda (1962–2023), showing that elite cohesion is one of the most consistent long-run determinants of fiscal performance. Chapter 4 extends the analysis to 42 Global South countries, finding that concentrated executive authority undermines revenue capacity, while inclusive elite arrangements strengthen it. The final two papers broaden the scope. Chapter 5 examines Uganda's 2018 vehicle import duty reform as a quasi-carbon tax, introducing the idea of a “tax-base double dividend”: environmental levies that expand fiscal space while modestly reducing emissions. Chapter 6 conducts a meta-regression of bunching-based elasticity of taxable income estimates, revealing heterogeneity and selective reporting that call into question the reliability of widely used methods. Together, the five studies recent politics in fiscal analysis, adapt tax design to low-capacity contexts, and interrogate core empirical methods—showing that durable DRM requires technical reforms aligned with inclusive political settlements and methodologically rigorous evaluation.