Supreme Court Acquits Death Row Convict: Nationwide Guidelines on DNA Evidence - An Indian and International Perspective

Index of Headings

1. Introduction
2. Case Background
3. Key Supreme Court Observations
4. The Court’s New Nationwide Guidelines
5. Broader Context: DNA Evidence in Indian Criminal Justice
6. Significance of the Judgment
7. International Perspective on Forensic DNA Evidence
8. Comparative Analysis: India vs. Global Standards
9. Road Ahead: Implementation and Reform
10. Conclusion
11. FAQs

Introduction

On July 15, 2025, the Supreme Court of India issued a landmark judgment that acquitted a man on death row after identifying grave errors in the collection and handling of crucial DNA evidence. This verdict did not merely correct a miscarriage of justice but also broke new ground by issuing comprehensive, binding guidelines for the collection, preservation, and processing of DNA and other biological materials in criminal investigations nationwide.

This judgment stands as a turning point in India’s forensic and criminal justice systems, drawing attention to persistent weaknesses, the dangers of wrongful conviction, and the pressing need for procedural reform. This article explores the case and the court’s guidelines, while placing India’s forensic DNA practices within an international framework and providing critical analysis, best practices, and future recommendations.

Case Background

The case arose from a heinous double homicide and rape in Tamil Nadu in 2021. The accused, Kattavellai alias Deevakar, was convicted and sentenced to death by the trial court, and the conviction was upheld by the Madras High Court. The prosecution rested its case almost entirely on DNA evidence, which was central to proving the accused’s involvement. However, on appeal, the defense highlighted systemic flaws during the police investigation, especially concerning the collection, storage, and documentation of DNA samples. These included an undocumented chain of custody, unexplained delays in sending samples to forensic laboratories, and improper storage that raised questions about possible contamination.

The bench quoted: 
“Someday, the courts, especially the Constitutional Courts, will have to take a call on a peculiar situation that arises in our justice delivery system. There are cases where clean acquittal is granted by the criminal courts to the accused after very long incarceration as an undertrial. When we say clean acquittal, we are excluding the cases where the witnesses have turned hostile or there is a bona fide defective investigation. In such cases of clean acquittal, crucial years in the life of the accused are lost. In a given case, it may amount to violation of rights of the accused under Article 21 of the Constitution which may give rise to a claim for compensation.” (para 46)

The Supreme Court, upon examining the case, found these procedural lapses so significant that the reliability of the DNA evidence was fatally compromised, leading to the accused's acquittal.

Key Supreme Court Observations

The apex court was emphatic about the consequences of poor investigative practices, making clear that the lack of a proper chain of custody, delays in processing, and inadequate storage fatally undermined the credibility of the scientific evidence.

It emphasized that DNA evidence must be preserved in pristine condition, since even minor procedural failures could jeopardize both the defense and the prosecution. Importantly, the court found the absence of uniform standards across Indian states for the handling of DNA evidence to be unacceptable, especially given the high stakes involved in criminal trials, particularly those involving the death penalty.

The Court’s New Nationwide Guidelines

In response to the gaps exposed by the case, the Supreme Court issued detailed and binding protocols for handling DNA evidence in criminal investigations across India.

Collection of DNA samples must now occur with the highest degree of care, with meticulous documentation at every step. The details recorded must include the First Information Report (FIR), the relevant law, data on the investigating officer and medical personnel, and, where possible, include signatures of all present. Efforts to involve independent witnesses must also be noted, and if not feasible, a formal written explanation is required.

Investigating Officers are responsible for ensuring swift logistics. All DNA samples must be transported to police stations or hospitals and then to forensic laboratories within 48 hours. Any delay exceeding this timeline must be justified in the case diary, and proper preservation of samples according to the best practices for each biological material—must be ensured at all times.

To remove any possibility of tampering, no package containing DNA evidence can be opened or resealed except by order of the trial court and only following a written request providing certified reasons.

One of the most significant reforms is the creation of a mandatory Chain of Custody Register. Every movement and every transfer of DNA evidence, from collection to trial, must be logged and justified in this register, which becomes part of the formal trial record. If records are incomplete, the Investigating Officer is required to provide an account of any lapses.

Broader Context: DNA Evidence in Indian Criminal Justice

DNA fingerprinting made its judicial debut in India in the early 1990s. Since then, its acceptance by courts has grown, and it is increasingly used in cases involving serious crimes, such as homicide, rape, and terrorism.

However, India still faces significant obstacles. There is no unified, nationwide legal framework specifically governing DNA evidence, as the DNA Technology Regulation Bill remains stalled in Parliament. Infrastructure is another challenge - India currently has about 30 state and centrally-funded forensic laboratories able to process DNA samples, resulting in vast backlogs and uneven access. According to a report by NITI Aayog, as of 2022, over 60% of Indian districts did not have timely access to advanced forensic facilities, and in some states, DNA test results took up to six months.

Significance of the Judgment

The new Supreme Court guidelines represent the most comprehensive articulation of due process standards for forensic evidence in the country’s history. They are designed to bring Indian practices closer to international standards by demanding scientific rigor, procedural uniformity, and transparency.

Importantly, the decision highlights the risk of wrongful conviction. Globally, flawed handling of DNA evidence has been a leading cause of wrongful convictions—according to the Innocence Project in the United States, over 375 people have been exonerated since 1989 primarily due to DNA evidence, with investigative lapses cited in over half of those cases. India’s new protections aim to prevent similar miscarriages of justice.

International Perspective on Forensic DNA Evidence

In the United Kingdom, the National DNA Database was established in 1995 with strict protocols for consent, storage, and the use of biological materials. Legislation governs what samples can be collected, how long profiles may be retained (especially after acquittal), and who can access data. The UK has routinely audited chain of custody systems, with stringent roles reserved for laboratories and police.

The United States operates the Combined DNA Index System (CODIS), with detailed federal and state regulations. Laboratories must be accredited, and processes for collecting, transporting, and logging evidence are codified in law. Courtroom admissibility is guided by the “Daubert standard,” which requires scientific validity and reliability. Recent Justice Department statistics show that as of 2023, more than 2 million DNA profiles have been processed in the US, and DNA evidence contributed to solving over 38,000 crime cases over five years. However, DNA mishandling remains a leading cause of wrongful conviction; the National Registry of Exonerations notes that in over 20% of U.S. wrongful convictions overturned by DNA evidence, contamination or errors in storage or documentation played a significant role.

Other jurisdictions, such as European Union countries, Australia, and Canada, also enforce central laws governing how DNA evidence is collected, stored, and destroyed. These countries place a premium on privacy, scientific rigor, and independent oversight.

Comparative Analysis: India vs. Global Standards

Compared to the UK, USA, and Australia, India, until now, has had a fragmented legislative framework for DNA evidence. Forensic infrastructure in India is limited and mostly concentrated in metropolitan areas. Chain of custody practices have often been inconsistent or non-existent, in contrast to mandatory, standardized protocols abroad.

Privacy protections are minimal, since supportive legislation is still pending. Training and awareness programs for police and forensic personnel are uneven, often depending on local resources. Judicial scrutiny has become increasingly reformist, especially since 2010, but lower courts still sometimes admit forensic evidence without adequate inquiry into chain of custody or scientific integrity.

The Supreme Court’s recent guidelines signal a marked shift toward international best practices, but the real test will be in their implementation—through expanded infrastructure, legislated privacy protections, and sustained professional training.

Road Ahead: Implementation and Reform

The success of these reforms will depend on several factors. First, early passage of the DNA Technology Regulation Bill will provide the legislative muscle needed to safeguard both the scientific process and individual rights. Second, investments are urgently needed. As of 2022, India had one DNA laboratory for every 45 million people, compared to one for every 2 million in the United Kingdom and Australia, resulting in critical delays and backlogs. Funding and decentralization are essential to ensure DNA testing can be performed promptly and to a high standard nationwide.

Third, capacity-building must be prioritized, with regular and mandatory training for police, medical professionals, forensic experts, and the judiciary. Police training academies must adopt the new protocols as a formal part of their curricula.

Judicial vigilance will be equally important. Courts at all levels should demand strict adherence to chain of custody protocols and scrutinize expert forensic reports. Over time, the Supreme Court’s guidelines may prompt a culture shift—one in which both the prosecution and defense expect and demand scientific accuracy at every stage.

Lastly, public and professional awareness will help reduce myths and the risk of misuse. In the US and UK, public education and transparency campaigns have been shown to increase public trust in forensic evidence while also holding law enforcement accountable.

Conclusion

The Supreme Court’s 2025 judgment is a watershed for forensic science and criminal justice in India. By holding investigative lapses to account and mandating nationwide standards for collecting and processing DNA evidence, the Court has strengthened both the rights of the accused and the broader public’s faith in the justice system.

Reforms of this scale are not implemented overnight. Their success will depend on prompt legislation, significant resource allocation, continued judicial oversight, and constant vigilance against lapses. Drawing lessons from international experience, India can now harness DNA technology’s promise—not merely as an investigative tool, but as a vital safeguard for truth and justice. When scientific precision and legal integrity work together, the justice system moves towards delivering justice not just to victims, but to all.

FAQs

Q Why did the Supreme Court acquit the accused in the 2021 Tamil Nadu rape and murder case?
A - The Court found serious lapses in how DNA evidence was collected, stored, and documented.
Key issues included an undocumented chain of custody and delays in lab submission.
These flaws fatally compromised the reliability of the prosecution’s case.

Q How do other countries handle forensic DNA evidence compared to India?
A - Countries like the UK, USA, and Australia have strict laws for DNA collection, storage, and use.
They mandate accredited labs, chain of custody audits, and privacy protections.
These safeguards reduce errors and help prevent wrongful convictions.