Chain of Custody and Drug Cases: Why Broken Evidence Links Lead to Acquittal

In drug cases, the prosecution must prove not only that a sale or possession happened, but also that the illegal drug presented in court is exactly the same item seized from the accused. When police officers fail to follow the chain of custody requirements under Republic Act No. 9165, the Comprehensive Dangerous Drugs Act, the Supreme Court will not hesitate to acquit.

In People v. Turemutsa (G.R. No. 227497, April 10, 2019), the Court reversed a conviction for illegal sale of marijuana because the prosecution failed to account for the seized drug from the moment of confiscation to its examination in the crime laboratory. The ruling is a firm reminder that procedural lapses in handling evidence can be fatal to the State's case.

The Facts of the Case

On March 26, 2005, police officers in Puerto Princesa City conducted a buy-bust operation against Dioscoro Comoso, who was suspected of selling marijuana. A civilian asset acted as the poseur-buyer. After the transaction, the arresting officer marked the plastic sachet and the buy-bust money with his initials. The seized items were inventoried, but the forensic chemist only received them on April 8, 2005 — about two weeks after the seizure.

Comoso was charged with violation of Section 5, Article II of RA 9165 for the illegal sale of dangerous drugs. The Regional Trial Court convicted him and imposed life imprisonment and a fine of P500,000. The Court of Appeals affirmed, but the Supreme Court reversed and acquitted him.

The Issue: Was the Chain of Custody Broken?

The sole issue was whether the prosecution proved Comoso's guilt beyond reasonable doubt despite not strictly complying with the requirements for preserving the integrity and evidentiary value of the seized drugs.

The Court answered no.

The Ruling: Gaps in Custody Create Reasonable Doubt

To convict in a drug case, the prosecution must prove two elements: (1) that the sale or transaction actually took place, and (2) that the corpus delicti — the illegal drug itself — was presented in court. The second element requires strict compliance with Section 21 of RA 9165, as amended by RA 10640.

Section 21 requires the apprehending team to conduct a physical inventory and photograph the seized items immediately after seizure, in the presence of the accused or his representative, an elected public official, and a representative of the National Prosecution Service or the media. The seized drugs must also be submitted to the forensic laboratory within 24 hours.

In this case, the Court found several fatal gaps:

• The inventory was not shown to have been conducted in the accused's presence, and there was no evidence that he signed it.
• No photographs of the seized items were taken, and no justification was offered for this omission.
• The required witnesses — an elected public official and a representative of the media or the National Prosecution Service — were not shown to have been present, even though this was a pre-planned operation.
• The seized items were delivered to the forensic chemist only after 10 working days, far beyond the 24-hour period required by law, with no explanation for the delay.

The Court emphasized that noncompliance may be excused only under justifiable grounds, but the prosecution must prove two things: first, that justifiable grounds existed, and second, that the integrity and evidentiary value of the seized items were preserved despite the lapse. The prosecution offered neither.

Presumption of Regularity Cannot Save a Flawed Case

The Office of the Solicitor General argued that the police officers should be presumed to have regularly performed their duties. The Court rejected this. The presumption of regularity applies only when nothing in the record suggests that law enforcers deviated from standard procedure. Where the official act is irregular on its face, the presumption cannot arise.

The Court also noted that the confidential informant, who also acted as the poseur-buyer, was never presented in court. While the arresting officer testified that he witnessed the transaction, the gaps in the chain of custody remained unexplained, creating reasonable doubt on whether the drug tested by the chemist was the same item seized from the accused.

Why Strict Compliance Matters

The Court explained that narcotics are not readily identifiable by sight. They can easily be mistaken for everyday objects, adulterated, substituted, or planted. Because the amounts seized are often minuscule, courts must apply heightened scrutiny. When the chain of custody is broken, there is no guarantee that the evidence has not been tampered with, and the prosecution fails to prove guilt beyond reasonable doubt.

Practical Takeaways

• Chain of custody is the backbone of drug prosecutions. Every link — from seizure and marking, to turnover to the investigating officer, to delivery to the forensic chemist, and finally to presentation in court — must be established.
• The 24-hour rule matters. Seized drugs must be submitted to the forensic laboratory within 24 hours. Unexplained delays create reasonable doubt.
• Inventory and photographs are mandatory. The inventory must be conducted in the presence of the accused and the required witnesses, and photographs must be taken. Noncompliance must be justified with concrete reasons, not vague assurances.
• The presumption of regularity is not a shield. Police officers cannot hide behind it when their actions visibly deviate from the requirements of Section 21.
• For accused persons, these rules are a defense. If the prosecution cannot account for the seized drugs at every stage, the case may fail regardless of the strength of the testimonial evidence.

This article is general information and not legal advice. For your specific situation, consult a lawyer or ask ASG Legal AI.