Reasonable Doubt Acquittal in Drug Cases Due to Broken Chain of Custody

In a significant ruling on drug prosecutions, the Supreme Court reversed a conviction for illegal sale of shabu because the police failed to preserve the chain of custody of the seized drugs. The case of People v. Catalan (G.R. No. 189330, November 28, 2012) illustrates that even when a buy-bust operation appears successful, the prosecution must still prove every link in the chain of custody beyond reasonable doubt. The Court emphasized that the presumption of regularity in police duty cannot override the constitutional presumption of innocence.

The Case

Louie Catalan was arrested in February 2004 after a buy-bust operation in San Pedro, Laguna. A police officer acting as poseur-buyer claimed Catalan sold him a plastic sachet of shabu for P100.00. The Regional Trial Court convicted Catalan of violating Section 5 of Republic Act No. 9165 (Comprehensive Dangerous Drugs Act of 2002) and sentenced him to life imprisonment with a P500,000.00 fine. The Court of Appeals affirmed the conviction.

Catalan appealed to the Supreme Court, arguing that the prosecution failed to establish the identity of the prohibited drug — the corpus delicti of the crime.

The Issue

The central question was whether the prosecution proved Catalan's guilt beyond reasonable doubt despite serious lapses in the chain of custody of the seized drugs.

The Ruling

The Supreme Court acquitted Catalan. The Court found that the buy-bust team committed several fatal procedural lapses that broke the chain of custody.

First, the marking of the seized sachet was done by the investigator, not by the arresting officer who had initial custody. The arresting officer failed to describe the circumstances of how and when the marking was made, leaving doubt as to whether the accused witnessed it.

Second, no representative from the media, the Department of Justice, or any elected public official was present during the seizure and inventory, as required by Section 21(1) of Republic Act No. 9165 and its Implementing Rules and Regulations.

Third, the prosecution did not present the investigator as a witness to validate the marking in court.

Fourth, the buy-bust team conducted no physical inventory and took no photographs of the seized drugs.

The Court noted that while the IRR contains a saving proviso for non-compliance, it applies only when the arresting officers acknowledge their lapses and offer a plausible explanation. In this case, the police neither admitted nor explained their failures.

The Presumption of Regularity

The Court also corrected the lower courts' reliance on the presumption of regularity in the performance of official duty. This presumption cannot prevail over the stronger presumption of innocence. Where the records show serious lapses by the police, there is no factual basis for presuming they performed their duties regularly.

Practical Takeaways

• Chain of custody is essential. In drug cases, the prosecution must prove an unbroken chain from seizure to court presentation. Any substantial gap raises reasonable doubt.
• Marking matters. The arresting officer who takes initial custody should mark the seized items, and the circumstances of marking must be clearly established.
• Witnesses are required. The presence of media, DOJ representatives, or elected officials during inventory is not a mere formality — it protects the integrity of the evidence.
• Presumption of regularity is not automatic. Courts cannot presume police regularity when the record shows unexplained procedural lapses.
• The saving proviso has limits. Non-compliance with Section 21 may be excused only if the police acknowledge the lapse and provide a justifiable explanation.

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