The promulgation of Law Number 1 of 2023 concerning the Criminal Code (KUHP) marks a historic departure from the colonial-era Wetboek van Strafrecht (WvS), positioning Indonesia within a new epoch of national criminal jurisprudence. Set to take full effect on January 2, 2026, this legislation attempts to bridge the ontological gap between formal state law and the sociological reality of the Indonesian people through the formal recognition of “living law” (laws that live in society), commonly equated with adat or customary law. This paradigm shift, encapsulated in Article 2 of the new code, seeks to balance the rigidity of the principle of legality with the fluid demands of substantive justice. However, the transition from a purely positivist system to one of sanctioned legal pluralism introduces profound complexities for legal practitioners, ranging from the evidentiary challenges of proving unwritten norms to the constitutional risks of inconsistent interpretation and potential human rights infringements.
The Doctrinal Transformation of the Principle of Legality
At the core of modern criminal law lies the principle of legality, or nullum delictum nulla poena sine praevia lege poenali, which dictates that no act is punishable unless prohibited by a pre-existing written law. This principle, enshrined in Article 1 paragraph (1) of the 2023 KUHP, serves as the bedrock of legal certainty and a shield against the arbitrary exercise of state power. Yet, the new code introduces a “material” dimension to legality in Article 2, which stipulates that the formal requirement for written law does not preclude the validity of the living law that determines an individual deserves punishment, even for acts not explicitly regulated by the state code.
This duality represents a compromise between two major schools of thought: legal positivism, which prioritizes the state’s monopoly on law-making, and sociological jurisprudence, which views law as an organic reflection of social behavior. The “living law” under Article 2 specifically refers to adat criminal law. For practitioners, this creates a bifurcated legal reality where an act can be lawful under the national statute but unlawful under regional customary norms, or vice-versa.
Mathematical Modeling of Legal Legitimacy and Certainty
The tension introduced by Article 2 can be analyzed through a trade-off model between Legal Certainty (CL) and Substantive Justice (JS). If Lf represents formal legality and Lm represents material legality, the perceived legitimacy (P) of the judicial system can be expressed as:
P=∫(αCL(Lf)+βJS(Lm))dt
In the colonial-influenced regime, α was the dominant coefficient, ensuring high predictability but often resulting in a “justice gap” where communities felt the state law was alien to their values. The 2026 framework increases β, attempting to minimize this gap, yet it risks decreasing CL due to the localized and unwritten nature of Lm.
The Regulatory Framework: PP 55 of 2025 and the Role of Regional Governance
The implementation of Article 2 is not intended as an unregulated invitation for unwritten norms to be applied arbitrarily. Instead, the state has mandated a process of “positivization” or codification through Regional Regulations (Peraturan Daerah or Perda). This requirement is intended to mitigate the risks of legal uncertainty by forcing unwritten traditions into a written, documented format.
Government Regulation (PP) Number 55 of 2025 serves as the operational guide for local governments to identify and enact these customary norms. The regulation establishes strict criteria for what may be considered a valid “living law” for the purpose of criminal enforcement:
- The norm must be consistent with the values of Pancasila and the 1945 Constitution.
- It must comply with universal human rights and general principles of law recognized by the community of nations.
- The norm must be actively recognized and implemented by the specific Customary Law Community (Masyarakat Hukum Adat).
- Crucially, the act must not already be regulated as a crime within the national KUHP itself.
The Standardization of Customary Sanctions
A significant innovation in PP 55 of 2025 is the limitation placed on adat sanctions. To prevent the imposition of cruel or inhumane punishments, the regulation restricts customary penalties to the “fulfillment of customary obligations” (pemenuhan kewajiban adat).
| Sanction Type | National Code Equivalent | Regulatory Limit (PP 55/2025) |
| Personal Customary Obligation | Category II Fine | Equivalent to a maximum of Rp10,000,000. |
| Corporate Customary Obligation | Corporate Fine | Regulated according to specific sectoral laws. |
| Restorative Action | Judicial Pardon | Can lead to dismissal of the case if fulfilled. |
While this standardization protects human rights, it arguably alters the “magical-religious” and restorative essence of traditional adat law, which often relies on symbolic actions rather than monetary values to restore cosmic and social balance.
Regional Landscape: Progress and Obstacles in Banten and Tangerang
The successful implementation of Article 2 in 2026 relies heavily on the administrative readiness of regional governments to map their local “living law.” In the Banten Province, home to distinct customary groups such as the Baduy (Urung Kanekes) and the Sabaki (Banten Kidul), this process is complex.
Status of Adat Legislation in Banten Province
Banten has established some groundwork through Regional Regulation No. 2 of 2022, which focuses on the institutional structure and leadership of Adat Villages. This regulation provides a legal framework for the existence of “Desa Adat,” allowing for the identification of customary leaders who would ideally serve as the primary sources for mapping adat crimes. However, as of late 2025, Banten’s legislative focus has been primarily on the Long-Term Development Plan (RPJPD 2025-2045) and Cultural Promotion (Perda No. 2 of 2024), rather than the specific criminalization of adat offenses as defined by the new KUHP.
In the Tangerang Regency, the situation reflects an urban-rural hybridity. While Tangerang has Perda No. 6 of 2018 on Regional Culture, which imposes administrative sanctions for cultural violations, the drafting of specific “Living Law” Perdas is still in the academic research phase. The challenge in Tangerang lies in the diffusion of norms; as an urbanized area with significant migration, the “living law” is often fragmented and lacks the territorial cohesion found in the more secluded Baduy communities.
The Process of Mapping and Academic Drafting
The creation of an Adat Perda requires a rigorous “Naskah Akademik” (Academic Draft) that justifies the inclusion of a customary norm based on philosophical, sociological, and yuridis (legal) foundations.
| Stage of Implementation | Action Required | Responsible Party |
| Identification | Mapping of active customary norms and territorial boundaries. | Local Government & Adat Institutions. |
| Verification | Ensuring norms do not violate HAM or Pancasila. | National Legal Development Agency (BPHN) & MoLaw. |
| Codification | Drafting and enacting the Regional Regulation (Perda). | Regional Legislature (DPRD) & Pemda. |
| Integration | Training police, prosecutors, and judges on local Perdas. | Supreme Court, Attorney General, Police. |
Failure to complete this mapping before January 2, 2026, could lead to a “legal vacuum” where courts are theoretically empowered by the KUHP to apply living law, but lack the formal regional regulations to do so with certainty.
Potential for Multiple Interpretations and Legal Conflict
The shift toward material legality introduces significant interpretive risks. The phrasing of Article 2 and its relationship with other laws may lead to inconsistent judicial outcomes across the archipelago.
Ambiguity of the “Living” Criterion
Sociologically, the “living law” is dynamic and often evolves faster than the legislative process. If a customary norm is codified into a Perda, it effectively becomes “positive law,” potentially freezing a tradition that the community itself may have already moved past. Critics argue that this process “state-ifies” adat law, causing it to lose its organic character and independent sovereignty.
Collision with National Special Laws
A major challenge for practitioners is the potential for overlapping jurisdictions between adat Perdas and national special laws (lex specialis). Many acts traditionally regulated by adat—such as domestic violence, child-related disputes, or sexual behavior—are now strictly governed by national statutes:
- Law on Elimination of Domestic Violence (UU PKDRT).
- Law on Sexual Violence Crimes (UU TPKS).
- Law on Child Protection.
Article 2 stipulates that living law applies only if the act is “not regulated in this law”. However, the ambiguity lies in whether this refers only to the KUHP or all national legislation. If a sexual offense is prosecuted under an adat Perda rather than the UU TPKS, the perpetrator might only face a Category II fine (Rp10 million) instead of years of imprisonment. This creates a “justice loophole” that could be exploited to the detriment of victims.
The Subjectivity of the “Pancasila Filter”
The requirement that living law must conform to Pancasila and the 1945 Constitution acts as a “constitutional filter”. However, the interpretation of Pancasila values—particularly the principle of “Belief in the One and Only God”—can be highly subjective. In conservative regions, this could lead to the validation of local norms that criminalize private behaviors or religious minorities, even if those behaviors are protected under a more liberal interpretation of national human rights.
Challenges for Legal Practitioners: Evidence and Procedure
The integration of living law into the state judicial system places a heavy burden on investigators, prosecutors, and judges who must navigate unwritten or newly codified local norms.
The Evidentiary Burden (Beban Pembuktian)
In a standard criminal trial, the prosecutor must prove the elements of the crime beyond a reasonable doubt. When dealing with Article 2, the prosecutor must additionally prove that:
- The norm exists and is “living” in the community.
- The defendant belongs to or performed the act within the specific territory of that community.
- The act violates the community’s sense of justice.
According to the rules of procedure, this often requires expert testimony from legal anthropologists or adat elders. However, not all adat institutions have the capacity or legitimacy to provide objective evidence, particularly in regions where customary leadership is contested.
Judicial Discretion and SEMA No. 1 of 2026
The Supreme Court has issued SEMA Number 1 of 2026 to guide judges through the complexities of the 2023 KUHP and the revised 2025/2026 Criminal Procedure Code (KUHAP). The SEMA encourages judges to move beyond being “mouthpieces of the law” to becoming arbiters of substantive justice.
Key procedural directives for judges include:
- Restorative Justice Prioritization: If a conflict has already been resolved via an adat council and the victim is satisfied, the judge should lean toward a “Judicial Pardon” (rechterlijk pardon), where the defendant is found guilty but no further state punishment is imposed.
- Offsetting Sanctions: Any customary punishment already served must be factored into the final sentencing to prevent double jeopardy or disproportionate punishment.
- Due Process of Law: Judges must ensure that unwritten norms do not violate the fundamental rights of the accused to a fair trial and the principle of non-retroactivity.
Despite these guidelines, the lack of a standardized national database of adat laws creates a high risk of inconsistent rulings. A judge in Pandeglang may interpret a customary norm differently than a judge in Tangerang, even if the underlying tradition is similar.
Prosecutorial Discretion and Perka 3/2023
The Attorney General’s Office (Kejaksaan Agung) has also prepared for this transition. Peraturan Kejaksaan Number 3 of 2023, while specifically focused on Papua, provides a template for national practice by allowing prosecutors to facilitate the ratification of Adat Court decisions by the District Court. If a settlement is reached at the adat level, the prosecutor may issue a Letter of Termination of Prosecution (SKP2) to maintain social harmony.
While this promotes efficiency, it introduces a risk of “informalization” where serious crimes could be settled through local power dynamics or payoffs, potentially bypassing the state’s duty to prosecute grave offenses.
Human Rights and Constitutional Risks
The most critical concerns regarding Article 2 involve the potential for discriminatory practices and the erosion of individual liberties.
Risks to Vulnerable Groups and Gender Equality
Customary laws in many parts of Indonesia are rooted in patriarchal structures. In matters of inheritance, marriage, or family honor, some adat systems may impose sanctions that are inherently discriminatory against women or children. For instance, if a local adat Perda recognizes “forced marriage” as a restorative solution for sexual violations, it directly conflicts with the national Law on Sexual Violence (UU TPKS) and international human rights standards.
The new KUHP explicitly states that living law must comply with HAM, but the mechanism for monitoring this at the regional level remains weak. Once a norm is enacted in a Perda, it carries the weight of state authority, potentially legitimizing discriminatory practices until they are eventually challenged and overturned by the Supreme Court—a process that is often too slow for the individuals involved.
The Conflict of Territoriality and Personal Status
Article 2(2) states that living law applies “in the place where the law lives” and applies to “every person” who commits an act there. This raises significant issues for travelers or migrants who may be unaware of specific local prohibitions. Unlike the national KUHP, which is publicized nationwide, local adat Perdas may not be easily accessible to outsiders, yet under the 2026 framework, ignorance of these local laws is not a defense. This creates a tension with the principle of lex certa (clear law), as individuals cannot reasonably foresee the legal consequences of their actions when moving between different administrative jurisdictions.
Strategic Synthesis: Navigating the 2026 Implementation
As the January 2026 deadline approaches, the Indonesian legal system stands at a crossroads. The recognition of living law is a significant step toward legal decolonization, but its success depends on the meticulousness of its implementation.
Recommendations for Legal Practitioners
To navigate this new landscape effectively, practitioners must adopt several strategic approaches:
- Contextual Mapping: Regional governments must prioritize the participatory mapping of adat norms, involving not just elders but also human rights advocates to ensure the resulting Perdas are constitutional.
- Harmonized Jurisprudence: The Supreme Court must actively curate and publish decisions involving Article 2 to build a “National Adat Jurisprudence” that provides a predictable standard for lower courts.
- Specialized Training: Police, prosecutors, and judges require “Cultural Competency” training to understand the nuances of the communities they serve, moving beyond a purely mechanical application of the law.
- Oversight Mechanisms: A robust, independent mechanism is needed at the Ministry of Law and Human Rights to review and “pre-filter” draft Adat Perdas before they are enacted, ensuring they do not contain discriminatory clauses.
Final Outlook
The 2023 KUHP’s embrace of Article 2 is an admission that the state cannot hold a total monopoly over the concept of “wrongdoing” in a nation as diverse as Indonesia. By integrating the living law, the state acknowledges that justice is often found not in the sterile words of a code, but in the restoration of relationships within a community. However, the transition in 2026 must be guarded by a fierce adherence to the principles of human rights and constitutional order.
The primary challenge for legal practitioners will be to ensure that “substantive justice” does not become a euphemism for “local arbitrariness.” Only through a rigorous process of codification, evidentiary proof, and judicial oversight can the living law truly enrich the national penal system without sacrificing the fundamental certainty that every citizen deserves from the law. The success of this transition will determine whether Indonesia has truly created a “National KUHP” or merely a fragmented system of localized justice.