This research examines the role of saksi mahkota or crown witnesses in the adjudication
of gambling crimes in Indonesia. Gambling remains a recurring issue that is often
difficult to prove due to limited legal evidence. The purpose of this study is to analyze
how the involvement of a crown witness, who is also a co-defendant, helps clarify the
facts and responsibilities in such cases. This research uses a normative legal method
based on statutory regulations, court decisions, literature, and interviews with legal
practitioners. Although crown witnesses are not explicitly regulated in Indonesian
criminal procedure law, they are recognized through Supreme Court jurisprudence such
as Decision Number 1986 K Pid 1989. The implementation of crown witnesses requires a
separation of case files, allowing one defendant to testify in another’s trial without
violating legal principles. Their role is especially important in gambling cases where
conventional evidence is often lacking. However, their testimony must be supported by at
least one other valid legal proof to maintain fairness and legal certainty. This study
implies the need for clear legal regulation to ensure the fair and consistent use of crown
witnesses while protecting the rights of defendants in the criminal justice process.