Carnio, Henrique Garbellini2025-12-092025-12-092025CARDOSO, Agatha Lorrana de Oliveira. A modulação de efeitos no direito tributário e a regulação econômica: uma análise sobre o re 574.706/PR a partir da análise econômica do direito (2017 a 2021). Goiânia (GO), 2025. 134 f. Dissertação (Mestrado Profissional em Direito Constitucional Econômico) - Centro Universitário Alves Faria, 2025.http://repositorio.unialfa.com.br/handle/123456789/697This dissertation focuses on the modulation of effects in Brazilian Tax Law in light of Economic Regulation and Economic Analysis of Law (AED). The object of the research is the decision handed down by the Supreme Federal Court (STF) in the trial of Extraordinary Appeal No. 574,706/PR, between 2017 and 2021, in which ICMS was excluded from the calculation basis of PIS and COFINS and the temporal effects of the decision were modulated. The guiding question is: to what extent does the STF decision in RE 574.706/PR, when modulating the effects of the exclusion of ICMS from the PIS and COFINS tax bases, reflect principles of the Economic Analysis of Law (AED) and Economic Regulation, and what are their implications for legal certainty, regulatory predictability, and the Brazilian competitive environment? The hypothesis is that this decision incorporates, even if implicitly, AED foundations, aimed at efficiency, mitigation of negative externalities, and protection of fiscal balance. The methodology used is the deductive method, based on a bibliographic review, document analysis, and case law. The results of the research demonstrate that the modulation of effects in the judgment of RE 574.706/PR operated, in addition to a procedural technique of temporality control, as a regulatory strategy with significant economic and institutional impacts. The analysis of documents and case law shows that the Supreme Federal Court, although without explicitly stating it, considered economic variables such as risks to tax collection, systemic effects on the public treasury and possible distortions of competition. The investigation also shows that the grounds invoked by the Court, especially those related to legal certainty and social interest, conceal rationalities of an economic nature compatible with the assumptions of the Economic Analysis of Law (AED) and the Theory of Regulation. Modulation, in this context, emerges as a tool of legal and fiscal governance, capable of influencing the stability of the regulatory environment, the behavior of taxpayers and the dynamics of sectoral competition. By examining the votes of the justices and the provisions of the decision, it is clear that the STF exercised an indirect regulatory function, assuming an active role in the management of externalities arising from its own case law, which broadens the field of understanding of the Court beyond the control of constitutionality stricto sensu. With this, the study contributes to a critical and expanded reading of modulation, understanding it as a public policy instrument exercised judicially.ptModulação de efeitosDireito tributárioÁnalise Econômica do Direito (AED)