Brasília faces a complex legal challenge as the country moves to implement a dual value-added tax system, with the Judiciary tasked with applying the spirit of “maximum utilization of existing regulations” to the new tax framework.
The Constituição Federal and Lei Complementar 214/2025 establish a regime involving the CBS and the IBS, which have essential identical characteristics.
The Incident of Resolution of Repetitive Demands (IRDR) can serve as a mechanism to build qualified judicial theses regarding the CBS and the IBS before the final word of the Supreme Federal Court (STF) or the Superior Court of Justice (STJ). Classified as a judgment of repetitive cases under art. 928 of the CPC, this process shifts the decision to Regional Federal Courts and State Courts, creating a thesis applicable to ongoing and future cases within their jurisdiction. The effect can later be extended nationally via a repetitive special or extraordinary appeal, under the conditions set forth in the law.
In the current division of competencies, Regional Federal Courts and State Courts may institute and judge the IRDR regarding the tax they enforce, under the conditions set forth in the law. Given the national character of the disputed rules, it is expected that higher courts will handle these as repetitive appeals, under the conditions set forth in the law. In this scenario, the thesis fixed in the final instance may be applied to the other exaction, if the circumstances allow.
This legal evolution also opens the door for the federative entity that will bear the indirect effect of the decision to participate as an amicus curiae, even if the incident is not being heard at a Regional Federal Court. Although debated, participation by the Union in this capacity at a State Court does not appear to displace jurisdiction based on the constitutional rule.
Expanding the dialogue and technical capacity
The process allows for the participation of a representative of excluded litigants, a role that in tax cases—often involving collective writs of security—appears destined for a labor union or association with judicial action on the issue and the technical capacity to represent it.
Furthermore, the IRDR provides for local procedural suspension, followed by the immediate right to request national suspension before the STF or STJ. This allows parties to avoid the formation of point-specific res judicata before the final definition of the thesis. The decision is improved by the requirement that the opinion cover all arguments, favoring or opposing, to identify the complete aspects of the controversy.
This requirement helps mitigate the “pragmatic inefficiency of theoretical judgments” identified by Conrado and Camano. These authors describe the “rebound litigation” where practical issues not solved by the model decision return to the Judiciary.
From a practical standpoint, the thesis formed through the IRDR is designed for the jurisdictional competence of the court that issues it. This creates a need for two uniformizing solutions. One is the direct classification of the issue as repetitive at higher courts for a thesis applicable nationwide, assuming it is the same legal question and the judicial bodies representing both taxes participate from the previous phase. Alternatively, the administration could apply the judgment’s determinative grounds to a theme not covered by the ruling if the circumstances allow, a possibility supported by specific legislation.
Administrative application of the thesis
Recent legislative updates support this administrative integration. Article 194-A of the Tax Code, added by Law Complementary 236/2026, establishes the observance of binding decisions. This provision fills a gap that could arise with the IBS. The rule mandates that the administration follow the precedents set by the Supreme Federal Court and the Superior Court of Justice.
The role of the IRDR in the new tax structure
The use of the IRDR appears adequate for forming mature and dialogic binding measures regarding the CBS and the IBS. The mechanism allows for uniformity across the tax system. It also supports the orderly participation of public and private actors with interests in the judicial discussions. The process ensures that the new dual value-added tax system functions with clear and consistent legal parameters.
