Chain of Custody in Drug Cases: Why Marking Seized Items Immediately Matters

In a significant ruling on the admissibility of evidence in drug cases, the Supreme Court reversed a conviction for illegal possession of shabu due to the prosecution's failure to establish an unbroken chain of custody over the seized drugs. The case of Lopez v. People (G.R. No. 188653, January 29, 2014) serves as a crucial reminder that in drug prosecutions, the prosecution must prove not only that the accused possessed the illegal substance, but also that the very item presented in court is the same one seized from the accused.

The Facts of the Case

On the evening of July 31, 2000, police officers implemented a search warrant at the house of Lito Lopez in Tabaco, Albay. During the search, officers recovered several plastic sachets containing white powder, aluminum foils, and other items suspected to be drug paraphernalia. A forensic chemist later confirmed that the seized items tested positive for methamphetamine hydrochloride, or shabu.

Lopez was charged with violation of Section 16, Article III of Republic Act No. 6425 (the Dangerous Drugs Act), for illegal possession of dangerous drugs. The Regional Trial Court convicted him, and the Court of Appeals affirmed the conviction. Lopez appealed to the Supreme Court, arguing that the identity and integrity of the seized items were not proven beyond reasonable doubt.

The Issue: Was the Chain of Custody Broken?

The central question before the Supreme Court was whether the prosecution had sufficiently established the chain of custody of the seized drugs. Lopez pointed out several gaps: the seized items were not marked immediately at the place of seizure, the markings were done only at the police station without clear testimony as to who made them, and there was no evidence showing who handled the drugs between the laboratory examination and their presentation in court.

The Ruling: Immediate Marking is Critical

The Supreme Court ruled in favor of Lopez and acquitted him. The Court emphasized that in drug cases, the existence of the drug itself is the corpus delicti—the body of the crime. Because illegal drugs are indistinct, not readily identifiable, and easily tampered with or substituted, the prosecution must show with certainty that the drug presented in court is the same drug recovered from the accused.

The Court reiterated the rule that marking of seized items should be done in the presence of the apprehended violator and immediately upon confiscation. This marking is the starting point of the custodial link. It serves to separate the marked evidence from all other similar items, preventing switching, planting, or contamination of evidence.

While the Court acknowledged that there are occasions when marking at the police station may be allowed, it noted that even a less-stringent application would not save the prosecution's case. In this instance, there was no categorical statement from any prosecution witness that markings were made at all, much less immediately upon confiscation or in the presence of the accused.

Substantial Gaps in the Chain

The Court identified several weaknesses in the prosecution's evidence:

• No immediate marking: The seized items were marked only at the police station, and no witness could definitively state who placed the markings.
• Uncertain identification: One police officer could not readily identify the plastic sachets he allegedly seized, while another identified them only by size—a basis the Court found unreliable.
• Missing photographs: Although witnesses claimed photographs were taken after the seizure, these were never presented in court.
• Unaccounted custody: There was no testimony on who had control of the seized items after the laboratory examination and before they were offered as evidence.

The Court cited its ruling in People v. Kamad (G.R. No. 174198, January 19, 2010), which outlined the four links that must be established in the chain of custody: (1) seizure and marking of the illegal drug by the apprehending officer; (2) turnover to the investigating officer; (3) turnover to the forensic chemist for examination; and (4) turnover and submission of the marked drug to the court.

Practical Takeaways

• Immediate marking is non-negotiable: Law enforcement officers must mark seized drugs at the place of seizure, in the presence of the accused, to establish the first and most critical link in the chain of custody.
• Document every transfer: Every person who handles seized drugs should be presented as a witness to testify on how they received the item, what they did with it, and how they transferred it to the next person in the chain.
• The presumption of regularity is rebuttable: Failure to immediately mark seized drugs raises reasonable doubt on the authenticity of the corpus delicti and can overcome the presumption of regularity in the performance of official duties.
• For defense lawyers: Look for gaps in the chain of custody—missing witnesses, unaccounted periods of custody, and unreliable identification are fertile grounds for challenging the prosecution's case.
• For accused persons: The identity and integrity of the seized drugs are not mere technicalities; they are constitutional safeguards that protect against planting of evidence and wrongful conviction.

The Lopez ruling underscores that in drug cases, the prosecution carries the heavy burden of proving not just possession, but the unbroken journey of the seized item from the accused to the courtroom. When that chain is broken, reasonable doubt arises—and the accused must be acquitted.

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