Regional economic integration in the East African Community commits partner states to eliminate internal tariffs and ensure the free movement of goods. In practice, however, states depend heavily on domestic taxation, and revenue authorities often adopt fiscal measures that conflict with regional law. This paper examines how courts have become central actors in resolving this tension. Through analysis of recent litigation before the East African Court of Justice and national courts, the study shows that judicial enforcement has translated treaty commitments into concrete economic rights for traders. The judgments reviewed reveal that courts are engaging in forms of judicial reasoning that closely resemble proportionality analysis, even though the doctrine is not expressly articulated when assessing whether national tax measures genuinely pursue public objectives or disguise protectionism. Building on this judicial trend, the paper proposes an explicit proportionality framework that would allow courts to balance fiscal autonomy with the integrity of the common market. The research suggests that proportionality provides a workable doctrinal bridge, offering states regulatory flexibility while protecting the legal certainty necessary for regional integration. The conclusion argues that formalising this standard may strengthen the EAC as a rule-based regional order, reducing reliance on political negotiation and reinforcing the binding nature of supranational law.
Ronald Serwanga (Tue,) studied this question.