Simon Butt – On 2 January 2026, Indonesia's new Code of Criminal Procedure (Kitab Undang-undang Hukum Acara Pidana, or KUHAP) came into force. The government has presented it as a historic break with a colonial and authoritarian past.
Whatever the official rhetoric, the new Code's substantive impact on the balance of power between citizens and the state is already being contested. Within days of the new Code taking effect, the first constitutional challenge was filed. By mid-January, at least 10 petitions had been registered at the Constitutional Court challenging provisions of the new Code and the related 2023 Criminal Code. More have followed. On 16 March, the Constitutional Court dismissed the first such challenge to be decided – not on the merits, but because the petitioners lacked legal standing. Other petitions are still pending.
This is the first of two articles examining the Code's evidence provisions, which make it much easier than before for the state to investigate, prosecute and ultimately convict its citizens. This article focuses on what now counts as evidence (almost anything). The next article turns to the evidentiary hurdles that the state must meet at each stage of the criminal process to obtain a conviction (almost nothing).
From five categories to eight
Article 184(1) of the Old Code recognised five types of valid evidence: witness explanations (keterangan saksi), expert explanations (keterangan ahli), documents (surat), 'indications' (petunjuk), and defendant explanations (keterangan terdakwa). Petunjuk was really an implication drawn from one of the other types of evidence, or, controversially, something else altogether. It was nebulous and difficult to pin down, and often seemed used to admit evidence that did not readily fit into the other types.
Article 235(1) of the new Code expands this list to eight. The 'explanation' and documentary categories are retained. Petunjuk has been removed. In its place, the Code adds four new and very broad categories: physical evidence (barang bukti); electronic evidence (bukti elektronik); judicial observation (pengamatan hakim); and a residual provision admitting 'anything that can be used for proof at trial so long as it is obtained lawfully'.
The new categories
Physical evidence has long featured in Indonesian criminal trials. However, Article 184(1) of the Old Code did not list it as a standalone evidentiary category. This meant that it could not 'count' towards a decision to investigate or to convict (more on this in part 2), unless it was somehow tied to another piece of valid evidence. Article 235(1)(e) now confirms it as evidence in its own right.
The status of electronic evidence – such as emails, messaging data and CCTV – has long been unclear under Indonesian law, with some judges admitting it as petunjuk and others refusing. Law 11 of 2008 on Electronic Information and Transactions (as amended) put an end to this uncertainty and inconsistency, making such evidence clearly admissible. Articles 235(1)(f) and 242 of the New Code put admissibility beyond doubt and broaden the category to include almost any conceivable type or medium of electronic information.
Judicial observation (pengamatan hakim) is the most conceptually novel of the new categories. Although not defined in the Code itself, it seems likely to be interpreted to cover a judge's direct observations during site inspections (descente), reconstructions, demonstrations of tools or weapons, and observations of a witness's demeanour.
But the category that most dramatically changes the evidentiary landscape is Article 235(1)(h) – a catch-all provision admitting anything that can be used for proof, so long as it is lawfully obtained. For more than four decades, Indonesia operated a closed system of evidence: material that did not fit one of the five statutory categories was not evidence. With Article 235(1)(h), Indonesia has shifted to an open system.
The counterbalances
The Code does include what appear to be counterbalances to this new open system. Article 235(5) says that evidence that a judge declares to be inauthentic or illegally obtained cannot be used at trial and has no evidentiary value. This is being widely described as Indonesia's first real statutory exclusionary rule.
On paper, this looks like a welcome departure from existing practice. Indonesian judges have historically been inconsistent: strict on documentary originals, but rarely scrutinising chain of custody or forensic provenance – despite well-documented problems with evidence that is lost, stolen, manipulated or obtained during illegal searches or investigations. Courts have tended to ignore these problems and convict regardless.
But in practice, this exclusionary rule may well not operate as a meaningful constraint, for at least three reasons.
First, a close reading of Article 235(3) suggests that judges are not, in fact, required to test authenticity at all. This provision says only that evidence must 'be able to be proven authentic' (harus dapat dibuktikan autentikasinya); it does not require that authenticity be established. Article 235(4) says judges 'have the power' (berwenang) to assess authenticity but does not say they must exercise it. Article 235(5) excludes evidence only when it has been 'declared by a judge' (dinyatakan oleh Hakim) to be inauthentic, and does not require any such declaration to be made.
Second, the exclusionary rule in Article 235(5) only operates at trial. But many of the decisions that carry the greatest practical consequences for a suspect, such as being designated a suspect, arrested or detained, happen well before trial. The exclusionary rule does not reach those stages, and the pretrial review mechanism (praperadilan) (discussed in my second article) has never required judges to test the probative value of evidence.
Third, even where the exclusionary rule does apply, it may be applied selectively. Writing extramurally in MariNews, Supreme Court judge Pudjoharsoyo has argued that Article 235(5) is not absolute. It gives judges only a discretion to exclude illegally-obtained evidence, he says, and prosecutors can resist exclusion by making 'proportionality arguments' (even though Article 235(5) makes no mention of proportionality).
On this reading, judges should weigh factors including the severity of the violation, its impact on the defendant's rights, the interests of law enforcement, and the availability of alternative remedies. While judges in many other countries perform similar balancing exercises, there are reasons to doubt that Indonesian judges will genuinely engage in such an analysis. Indonesian judges often fail to provide adequate legal reasoning, and have failed to engage in proportionality analysis in other areas of law.
It is not difficult to imagine a panel underplaying the significance of an arrest without a warrant, or even a coerced confession, when otherwise convinced of guilt.