This study examines the generic structure of substance-based judgments of Nigerian Supreme Court lead judges. Data consist of fifteen purposively sampled judgments, qualitatively analysed using the generic structure potential approach and the transitivity system. The result shows that the analysed judgments have thirteen macro-structural elements which comprise nine obligatory and four optional elements, realised through major and minor process clauses. The obligatory elements circumscribe the lead judges to their discourse community norms while the optional elements in the judgments are instances of contextual variation in the analysed genre.
