The Evidentiary Strength of Blockchain Transactions as Electronic Evidence in the Indonesian Criminal Procedure Law System

Figure Ilustration AI

FORMOSA NEWS - Yogyakarta - Blockchain Transactions Hold Conditional Power as Legal Evidence in Indonesian Criminal Courts. Data recorded on blockchain networks can serve as valid electronic evidence in Indonesian criminal proceedings, but its legal strength depends on supporting real-world proof. This key finding comes from a study published in July 2026 by legal scholars Aloysius Wisnubroto and Winarno from Universitas Atma Jaya Yogyakarta. Published in the Formosa Journal of Applied Sciences, the research highlights how digital traces on decentralized ledgers can help law enforcement prosecute cryptocurrency-related crimes, including ransomware, fraud, and money laundering, provided investigators connect anonymous digital wallets to real-world identities.

The Legal Gap in Modern Digital Crime Investigations
Cryptocurrency transactions and decentralized finance have reshaped global financial systems, but they have also introduced sophisticated methods for cybercrime. Modern criminal activities frequently leave technical footprints across blockchain networks. Features like cryptographic security, automated timestamps, and permanent records make blockchain data highly resistant to unauthorized alteration. However, traditional legal frameworks in Indonesia primarily governed by the Indonesian Criminal Procedure Code (KUHAP) were written before the rise of digital assets. While KUHAP recognizes conventional evidence such as witness testimony, expert opinions, and physical documents, it does not explicitly mention transaction hashes, digital wallet addresses, or distributed ledgers. Although recent updates to Indonesia's Electronic Information and Transactions Law (UU ITE) accept electronic documents as legal evidence, courts still face complex challenges when determining the exact probative weight of decentralized blockchain data in criminal trials.

Examining Digital Evidence Through Legal Methodology
To evaluate how blockchain records fit into Indonesian criminal procedure, the researchers applied a normative legal research methodology. They analyzed relevant legal statutes, legal doctrines, and procedural requirements governing digital evidence handling. The study utilized two primary analytical approaches:

• Statutory Approach: Examining the provisions of KUHAP alongside Law Number 1 of 2024 (the updated UU ITE) to establish the normative legal basis for electronic evidence.
• Conceptual Approach: Evaluating how core legal concepts such as data authenticity, information integrity, relevance, and chain of custodyapply to the technical structure of blockchain transactions.

Through qualitative descriptive analysis, the authors mapped out how technical facts generated on-chain must be translated into legally admissible proof in a courtroom setting.

Key Findings on Blockchain's Evidentiary Weight
The analysis by the Universitas Atma Jaya Yogyakarta researchers reveals several critical insights regarding the legal status of blockchain data:

• Legal Admissibility: Blockchain transaction data is legally admissible as Electronic Information or Electronic Documents under Indonesian criminal procedure law.
• Pseudonymity Limits Direct Attribution: A transaction hash proves that a digital asset transfer occurred between two wallet addresses at a specific time. However, because public blockchains use alphanumeric wallet addresses, the data alone cannot prove the real-world identity of the person controlling the wallet.
• Necessity of Off-Chain Evidence: On-chain data achieves its maximum probative strength when paired with off-chain corroborating evidence. This includes Know Your Customer (KYC) records from cryptocurrency exchanges, banking records, IP address logs, seized physical devices, and communication logs.
• Inadequacy of Simple Screenshots: Basic screenshots of blockchain explorers carry weak evidentiary value. Courts require comprehensive digital forensic reports that document the extraction method, verify data integrity, and remain reproducible by independent forensic experts.

Implications for Law Enforcement and Judicial Policy
The study's insights offer practical guidance for Indonesia's criminal justice system as digital asset adoption continues to grow. For law enforcement agencies and investigators, the research underscores the urgent need to establish standardized operational procedures for blockchain forensics. Proper chain of custody protocols must cover every stage of handling digital evidence, from identifying transaction hashes to generating formal forensic reports. For judges and prosecutors, the findings provide an analytical framework based on four core parameters: authenticity, integrity, attribution, and legal relevance. Judges are encouraged to adopt a balanced approach neither dismissing blockchain evidence due to technical complexity nor accepting technical charts without verifying their connection to the accused.

Author Profiles
Aloysius Wisnubroto Academic Role: Legal Scholar and Senior Researcher Affiliation: Universitas Atma Jaya Yogyakarta, Indonesia Field of Expertise: Criminal Procedure Law, Cybercrime Law, and Digital Evidence Evaluation.
Winarno Academic Role: Legal Scholar and Researcher Affiliation: Universitas Atma Jaya Yogyakarta, Indonesia Field of Expertise: Criminal Law, Information Technology Law, and Criminal Justice Systems.

Source

Aloysius Wisnubroto,  Winarno. The Evidentiary Strength of Blockchain Transactions as Electronic Evidence in the Indonesian Criminal Procedure Law System. Formosa Journal of Applied Sciences (FJAS). Vol. 5, No. 7, hlm. 1475-1492.
DOI: https://doi.org/10.55927/fjas.v5i7.73
URL: https://journalfjas.my.id/index.php/fjas