The postulate Nullum crimen sine lege, or the Principle of Criminal Legality, constitutes the cornerstone of modern Criminal Law and the Democratic Rule of Law. Located at the heart of fundamental guarantees, its primary purpose is to limit state punitive power, ensuring that no individual is criminally sanctioned without a prior, written, strict, and certain legal norm that describes the conduct as a criminal offense.
1. Definition, Concept, and Legal Nature
The principle Nullum crimen, nulla poena sine lege (there is no crime, nor punishment, without law) represents the guarantee that the State's penal intervention must be guided by strict legality. From a technical-legal perspective, it is a fundamental constitutional principle and an individual guarantee of a mixed nature: political, by limiting state arbitrariness; and legal, by acting as a validity criterion for the application of sanctions.
The legal nature of this institute transcends a mere rule of interpretation, consolidating itself as a first-dimension fundamental right. It unfolds into four essential sub-principles, according to the classical doctrine of Claus Roxin and Hans Welzel:
- Lex Praevia: Prohibition of the retroactivity of incriminating criminal law (non-retroactivity in pejus).
- Lex Scripta: Prohibition of customary law to establish or aggravate penalties (requirement of law in the strict sense).
- Lex Stricta: Prohibition of the use of analogy in malam partem to create crimes or increase sanctions.
- Lex Certa: Mandate of taxativity (certainty), requiring that the law describes the prohibited conduct in a clear and exhaustive manner.
2. Historical Origin and Evolution in Law
Historically, the genesis of the principle dates back to the Magna Carta of 1215 of King John of England, specifically in clause 39 (per legem terrae). However, its modern theoretical formulation is a fruit of the Enlightenment. Cesare Beccaria, in his work "On Crimes and Punishments" (1764), defended the need for clear and prior laws as an antidote to the judicial despotism of the Ancien Régime.
The Latin formulation Nullum crimen sine lege is attributed to the German jurist Paul Johann Anselm von Feuerbach, in the early 19th century, consolidated in the Bavarian Penal Code of 1813. On the international stage, the principle was enshrined in the Declaration of the Rights of Man and of the Citizen of 1789 (Article 8).
In Brazil, the principle has been present in all republican constitutions. The Criminal Code of the Empire of 1830 already provided in its Article 1: "There shall be no crime, nor punishment, that is not declared in a prior law." This tradition consolidated Brazilian Criminal Law as a Civil Law system, based on written codification and parliamentary reservation.
3. Exact Legal Provision
The normative foundation of the principle of legality in the Brazilian legal system is twofold, found at the top of the legislative hierarchy and in the fundamental penal norm:
- Federal Constitution of 1988: Art. 5, item XXXIX – "there is no crime without a prior law that defines it, nor punishment without prior legal commination."
- Brazilian Penal Code (Decree-Law No. 2.848/1940): Art. 1 – "There is no crime without a prior law that defines it. There is no punishment without prior legal commination."
- American Convention on Human Rights (Pact of San José, Costa Rica): Art. 9 – "No one shall be convicted for any act or omission that did not constitute a criminal offense, under the applicable law, at the time it was committed."
4. Practical Application and Jurisprudential Understanding
The practical application of Nullum crimen sine lege is frequently the subject of analysis by Superior Courts, especially regarding taxativity and the reservation of law.
4.1. Supreme Federal Court (STF)
The STF has consolidated the understanding that the principle of legality is a guarantee against the vagueness of penal norms. In the judgment of ADO 26 and MI 4733, which dealt with the criminalization of homophobia and transphobia, the Court faced a heated debate over strict legality. The court decided that legislative omission authorized the interpretation of the Racism Law (Law 7.716/89) to encompass acts of homotransphobia. Although criticized by some doctrinal sectors as an offense to nullum crimen sine lege, the ministerial majority understood it to be an interpretation in accordance with the Constitution in the face of an unconstitutional omission.
Another relevant point is Binding Precedent (Súmula Vinculante) 24, which establishes: "A material crime against the tax order, provided for in art. 1, items I to IV, of Law No. 8.137/90, is not typified before the final assessment of the tax." Here, legality conditions the very existence of the crime to the exhaustion of the administrative path.
4.2. Superior Court of Justice (STJ)
The STJ acts rigorously in the prohibition of analogy in malam partem. In Special Appeal (REsp) 1.631.850, the Court reiterated that incriminating penal norms do not admit extensive interpretation that harms the defendant, maintaining the integrity of legal reservation. Furthermore, the STJ has settled jurisprudence on the retroactivity of more beneficial penal law (lex mitior), according to Art. 2 of the CP, which is the logical reverse of the anteriority of penal law.
5. Related Principles and Doctrinal Divergences
The principle of legality does not operate in isolation, correlating with other guarantee-based axioms:
- Legal Reservation: It differs from legality in a broad sense. While legality admits infralegal acts (decrees, ordinances) for administrative purposes, legal reservation requires that penal matters be treated exclusively by Ordinary Law (or Complementary Law), prohibiting Provisional Measures from creating crimes (Art. 62, § 1, I, b, CF/88).
- Mandate of Taxativity (Determinability): Doctrinal divergence arises regarding "open penal types" and "blank penal norms." Part of the doctrine (such as Nilo Batista) criticizes the excessive use of heterogeneous blank penal norms, arguing that supplementation by Executive acts weakens nullum crimen sine lege.
- Fragmentarity and Subsidiarity: Criminal Law must be the ultima ratio, intervening only when other branches of Law fail to protect the legal interest.
6. Contemporary Relevance and Practical Impacts
In contemporary times, the principle faces challenges in the face of digital and economic crime. The need for laws that keep pace with technological evolution often clashes with legislative slowness, creating normative vacuums that cannot be filled by judicial decision under penalty of absolute nullity.
Recently, the discussion on Administrative Sanctioning Law (Administrative Improbity Law - Law 14.230/2021) imported concepts from nullum crimen sine lege, requiring specific intent and strict typicality, which demonstrates the expansion of this principle's influence beyond the Penal Code, informing the entire state ius puniendi.
In short, Nullum crimen sine lege remains the citizen's main shield against arbitrariness, ensuring that individual freedom can only be curtailed through rules previously established by the democratic legislative process, guaranteeing legal certainty and the predictability of social relations.
Legal and Jurisprudential References
- BRAZIL. Constitution of the Federative Republic of Brazil of 1988. Brasília, DF.
- BRAZIL. Decree-Law No. 2.848, of December 7, 1940. Penal Code.
- STF. Direct Action of Unconstitutionality by Omission (ADO) 26. Rel. Min. Celso de Mello, judged on 06/13/2019.
- STF. Binding Precedent 24. Brasília, DF.
- STJ. Precedent 231 (incidence of mitigating circumstance and minimum limit of the penalty).
- FEUERBACH, Paul Johann Anselm von. Lehrbuch des gemeinen in Deutschland gültigen peinlichen Rechts, 1813.
