Chain of Custody in Drug Cases: When Missing Witnesses Mean Acquittal

In drug cases, the prosecution must prove not only that the accused possessed illegal drugs, but also that the drugs presented in court are the very same items seized from the accused. This is the essence of the chain of custody rule. In Mariñas v. People (G.R. No. 232891, July 23, 2018), the Supreme Court acquitted a man convicted of illegal possession of shabu because the police failed to justify the absence of required witnesses during the inventory of the seized drugs. The case is a reminder that strict compliance with Section 21 of Republic Act No. 9165, the Comprehensive Dangerous Drugs Act of 2002, is crucial to a successful drug prosecution.

The Facts of the Case

On October 5, 2010, police officers in San Pedro, Laguna were conducting a follow-up operation on motorcycle theft when they saw two men in an alley, one showing the other a plastic sachet that appeared to contain shabu. When the officers approached and identified themselves, one man fled. The other, Lamberto Mariñas, was arrested. Inside the nearby house, police also saw another man holding a plastic sachet of shabu.

The seized sachets were brought to the police station, where they were marked, inventoried, and photographed. Only a media representative was present during the inventory; no elected public official or Department of Justice (DOJ) representative attended. Mariñas was charged with illegal possession of dangerous drugs under Section 11, Article II of RA 9165. The trial court convicted him, and the Court of Appeals affirmed.

The Issue

The central question was whether the prosecution had established an unbroken chain of custody over the seized drugs, as required by Section 21 of RA 9165, or whether the missing witnesses during the inventory created a substantial gap that warranted acquittal.

The Ruling

The Supreme Court ruled in favor of Mariñas and acquitted him. The Court held that the prosecution failed to provide justifiable grounds for the absence of an elected public official and a DOJ representative during the inventory of the seized items.

Under the version of Section 21 applicable in 2010, the physical inventory and photographing of seized drugs must be conducted in the presence of three witnesses: a representative from the media, a representative from the DOJ, and any elected public official. These witnesses must sign the inventory and receive a copy. The Court noted that while minor procedural lapses may be excused, the prosecution must prove that the arresting officers exerted earnest efforts to comply and that there was a justifiable ground for non-compliance.

Here, the prosecution offered no explanation for the missing witnesses. Citing People v. Umipang (686 Phil. 1024 [2012]), the Court emphasized that unjustified absence of required witnesses constitutes a substantial gap in the chain of custody, casting serious doubt on the integrity and identity of the corpus delicti—the drug evidence itself. The presumption of regularity in the performance of official duties cannot cure a gross disregard of procedural safeguards.

The Chain of Custody Rule Explained

The chain of custody rule requires the prosecution to account for the seized drugs from the moment of seizure up to their presentation in court. Each link must be accounted for to prevent switching, planting, or contamination of evidence. Key points from the ruling:

• Marking: In warrantless seizures, marking may be done at the place of arrest or at the nearest police station, whichever is practicable.
• Inventory and photography: Must be done in the presence of the required witnesses, who must sign the inventory.
• Witnesses: Under the original Section 21, three witnesses were required—media, DOJ, and an elected public official. Under RA 10640 (2014), this was reduced to two—an elected public official and either a DOJ or media representative.
• Non-compliance: May be excused only if the prosecution proves justifiable grounds and that the integrity of the evidence was preserved.

Practical Takeaways

• For law enforcement: Strictly comply with Section 21 of RA 9165. Document all efforts to secure the required witnesses, and if any are absent, state the justifiable reasons in sworn affidavits.
• For prosecutors: The burden is on the prosecution to explain any deviation from the chain of custody. Failure to do so can result in acquittal, even where other evidence points to guilt.
• For the defense: Examine the chain of custody closely. Missing witnesses, unexplained gaps, or inconsistent testimonies can create reasonable doubt.
• For the public: The rule protects against planting of evidence and ensures that the drugs presented in court are truly the ones seized.

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