The Principle of Legality: The Foundation of Justice and Legal Certainty

Legal Literacy - Learn about Principle of Legality, a principle criminal law that is essential. Learn about its application, history, and relationship with other legal principles.

The principle of legality is a fundamental principle in the criminal justice system that guarantees legal certainty and protects individuals from arbitrariness. This principle affirms that an act cannot be criminalized if it is not clearly regulated in the criminal law that was in force before the act was committed.

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The principle of legality has been known since the time of Ancient Rome with the phrase "nullum crimen sine lege, nulla poena sine lege" which means no crime without law, no punishment without law. This principle then developed in Continental Europe and was adopted by various countries, including Indonesia.

• Greek philosophers such as Plato and Aristotle discussed the concept of "legal certainty" and the importance of written rules.
• During the Athenian democracy, written laws were carved on wooden boards and displayed in public places so that everyone could know them.

• The phrase "nullum crimen sine lege, nulla poena sine lege" (no crime without law, no punishment without law) first appeared in Roman legal texts.
• This principle is enshrined in criminal law Roman law and became the foundation for the legal system in Continental Europe.

• The application of the principle of legality declined due to the influence of church law and feudal law, which were not always written.
• The Magna Carta (1215) in England is an early example of limiting the power of the king and affirming the principle that no one should be punished without due process of law.

• Philosophers such as Montesquieu and Beccaria re-emphasized the importance of legal certainty and the principle of legality.
• Rousseau's "social contract" theory states that laws are created with the consent of the people and must protect individual rights.

• The principle of legality is formally adopted in various constitutions and criminal codes in European countries.
• This principle has become an integral part of the modern legal system and is recognized as one of the fundamental human rights.

• The principle of legality was introduced in Indonesia through Dutch criminal law (Wetboek van Strafrecht voor Nederlandsch-Indië).
• Its application is not always consistent and is still influenced by customary law and colonial law.

• The principle of legality is adopted in the Indonesian Criminal Code (Criminal Code) which had been previously enacted in 1918.
• The 1945 Constitution and various other laws and regulations also affirm this principle.

The principle of legality is formulated in Article 1 paragraph (1) of the Criminal Code (KUHP) which states that "No act may be punished, except based on the provisions of the legislation in force at the time the act was committed." This formulation contains two important meanings:

1. No crime without law (nullum delictum sine lege): An act cannot be categorized as a criminal act if it is not clearly regulated in the criminal law.
2. No punishment without law (nulla poena sine lege): A person cannot be punished if there is no law governing the punishment for the act he/she committed.

• Article 1 paragraph (1): "No act can be punished unless it is based on criminal provisions according to the law that was made first."
• Focus: Formal legality principle only recognizes written law.
• Weaknesses:
  • Does not recognize unwritten law (customary law).
  • Limits the scope of judges in deciding cases.

• Article 1 paragraph (1): "No act may be subject to criminal sanctions and/or actions except for criminal acts in statutory regulations that existed before the act was committed."
• Article 2 paragraph (1): "The provisions as referred to in Article 1 paragraph (l) do not reduce the validity of the law that lives in society which determines that a person deserves to be punished even though the act is not regulated in this Law."
• Focus: Formal and material legality principles recognize written and unwritten law.
• Advantages:
  • Provides judges with room to maneuver in deciding cases by considering unwritten law.
  • Provides fairer legal certainty for perpetrators of criminal acts.

• Prohibition of Analogy: An act cannot be punished based on analogy with existing statutory regulations.
• Most Favorable Criminal Provisions: If there is a change in statutory regulations after the act is committed, the provisions that are most favorable to the perpetrator shall apply.

The principle of legality has several objectives and benefits, including:

• Providing legal certainty: The public knows with certainty what actions are prohibited and and threatened with criminal sanctions.
• Protecting individuals from arbitrariness: Law enforcement officials cannot take action against someone based on unclear interpretations or rules.
• Ensuring equality before the law: Everyone is treated equally under the law, without exception.
• Encouraging legal compliance: The public is more encouraged to comply with the law because they clearly know the consequences.

The principle of legality is applied in various aspects of criminal law, including:

• Investigation: Investigators can only conduct investigations into an act that is regulated as a criminal act in the law.
• Prosecution: Public prosecutors can only prosecute someone in court if their actions are regulated as a criminal act in the law.
• Examination in court: Judges can only decide cases based on applicable laws.

The principle of legality is closely related to the principle lex posterior which states that the applicable law is the most recent law. If there is a change in the law after an act is committed, then the principle of lex favorabilior applies, which means that the law most favorable to the defendant is applied.

Although the principle of legality is a fundamental principle, there are still several challenges in its implementation, including:

• Unclear formulation of laws: Imprecise formulation of laws can lead to multiple interpretations and open opportunities for arbitrariness.
• Rapid technological advancements: Rapid technological advancements can give rise to new types of criminal acts that are not yet regulated by law.

Therefore, continuous efforts are needed to improve the quality of legislation and strengthen the implementation of the principle of legality in the Indonesian criminal justice system. Thus, the principle of legality can truly become the foundation of justice and legal certainty for the entire society.