CONSTITUTIONAL MUTATION AND THE EXPANSION OF ERGA OMNES EFFECTS: THE PHENOMENON OF THE FEDERAL SENATE’S DISPLACEMENT FROM DIFFUSE CONSTITUTIONAL REVIEW

Abstract

This article critically examines the phenomenon of constitutional mutation as applied to Article 52, item X, of the 1988 Federal Constitution, which governs diffuse constitutional review in Brazil. The study analyzes how the jurisprudential interpretation developed by the Federal Supreme Court has expanded the erga omnes effectiveness of decisions rendered in diffuse review, even in the absence of participation by the Federal Senate, which constitutionally holds the prerogative to suspend the enforcement of statutes declared unconstitutional. This interpretive process is problematized from the perspectives of legislative dignity, legal certainty, and the separation of powers, highlighting risks to institutional stability among the branches of government. The analysis focuses on Habeas Corpus No. 127,900, demonstrating the expansion of the range of actors entitled to bring matters before the Supreme Court and the collateral normative effects arising from this constitutional mutation. Finally, the article argues for the need for regulatory measures and institutional debate to mitigate the undesirable effects of constitutional mutation, thereby preserving the legitimacy of the legal system and democratic participation in the constitutional change process.