The Latin expression ex tunc designates the retroactive effectiveness of a legal act, sentence, or judicial decision, causing its effects to reach facts prior to the moment of its issuance. With transversal application in Civil, Constitutional, and Administrative Law, the institute aims to restore the status quo ante, annulling legal situations as if they had never existed.
Concept and Foundation
The term ex tunc, translated literally as "from the beginning," qualifies the temporal effectiveness of an act or decision that operates with retroactive effects. It differs ontologically from the ex nunc (from now on) effect, which produces only prospective effects. The legal nature of the institute lies in restoring the soundness of the legal system, aiming at the annulment of flawed acts or the declaration of absolute nullity, thus operating with exhaustive force over the past.
Historical Origin and Evolution
The genesis of the concept dates back to Roman Law, consolidating itself in the maxim quod ab initio vitiosum est, non potest tractu temporis convalescere (what is flawed from the beginning cannot convalesce with the passage of time). The Romanistic tradition influenced the 1916 Civil Code and was fully incorporated by the 2002 Civil Code, in addition to structuring the theory of nullities in Brazilian Administrative and Constitutional Law, where the unconstitutionality of a norm is, as a rule, absolute and retroactive.
Legal Provision and Normative Framework
The national legal system enshrines the ex tunc effect in several statutes:
- Civil Code, art. 182: Establishes that, once a legal transaction is annulled, the parties shall be restored to the state in which they were before it.
- Code of Civil Procedure, art. 525, § 1, III: Refers to the unenforceability of an obligation based on a judicial title founded on a law or normative act declared unconstitutional by the Supreme Federal Court (STF).
- Law 9.868/1999 (ADI Law), art. 27: Although it authorizes the modulation of effects (making an exception to retroactivity), it reaffirms the general rule of absolute nullity with ex tunc effects in the declaration of unconstitutionality.
Practical Application and Jurisprudence
Within the scope of the Supreme Federal Court (STF), the rule is the declaration of unconstitutionality with ex tunc effects. However, in attention to the principle of legal certainty and the public interest, the Court has used the technique of modulation of effects (art. 27 of Law 9.868/99) to attribute ex nunc or proactive effects. Current jurisprudence, notably in the judgment of general repercussion themes, demonstrates growing caution in the application of absolute retroactivity when it puts the stability of economic and social relations at risk.
In Labor Law, TST Precedent (Súmula) 363 establishes that the hiring of a public servant without a public competitive examination is null, producing effects only regarding the payment of the agreed consideration and the amounts related to the FGTS (Severance Indemnity Fund), in a mitigated application of ex tunc nullity to avoid the illicit enrichment of the Public Administration.
Related Principles and Doctrinal Divergences
The main antagonist of ex tunc is the principle of legal certainty. Contemporary doctrine, led by names such as Gilmar Mendes and Luís Roberto Barroso, debates the tension between "absolute nullity" (which requires ex tunc) and the "theory of appearance" or "protection of legitimate trust." Divergences arise when retroactivity affects third parties in good faith, leading the STF to consolidate the understanding that the modulation of effects is a prerogative of the constitutional interpreter to mitigate the impacts of absolute nullity.
Contemporary Relevance and Impacts
The relevance of the institute remains central to the soundness of the Rule of Law. In times of intense judicialization, the definition of the temporal framework for the effectiveness of judicial decisions acts as a tool for social stabilization. The practical impact is felt directly in the management of judicial liabilities and the predictability of decisions, where the magistrate not only decides the merits but weighs the temporal extent of its effectiveness, balancing the justice of the specific case with the predictability of the system.
Legal and Jurisprudential References
- BRAZIL. Law No. 10.406, of January 10, 2002. Establishes the Civil Code. Art. 182.
- BRAZIL. Law No. 9.868, of November 10, 1999. Provides for the process and judgment of the direct action of unconstitutionality. Art. 27.
- STF. ADI 4.451/DF. Rapporteur Min. Ayres Britto. Discussion on modulation of effects and nullity.
- TST. Precedent (Súmula) No. 363. Null contract. Effects.
- BARROSO, Luís Roberto. Course on Contemporary Constitutional Law. São Paulo: Saraiva, 2023.
