Abstract:
This study juridically analyzes the system of evidence in Indonesian and Thai criminal procedure law, focusing on the
regulation and application of evidentiary instruments. It compares the formalistic and enumerative approach of Indonesia’s Criminal
Procedure Code (KUHAP), particularly Articles 183–184, which require a minimum of two lawful pieces of evidence—namely
witness testimony, expert testimony, documents, indications, and defendant statements—against Thailand’s more inclusive model
under Sections 226–231 of the Criminal Procedure Code (CPC), which classifies evidence into material, documentary, and personal
evidence and grants broader judicial discretion. Both systems share similarities, including the exclusionary rule against illegally
obtained evidence and the recognition of digital evidence in response to contemporary legal developments, particularly after
Indonesia’s reform through Law No. 20 of 2025. However, structural differences significantly affect the effectiveness of justice:
Indonesia emphasizes legal certainty to prevent judicial subjectivity, while Thailand promotes procedural flexibility and allows
private prosecution to enhance efficiency and victim participation. Employing a normative-comparative method, this study concludes
that ASEAN legal harmonization is necessary to develop a balanced hybrid evidentiary model capable of ensuring substantive truth
while safeguarding the human rights of suspects and defendants in the era of transnational crime.
