Supreme Court Guidelines on DNA Evidence

The Supreme Court of India, in the case Kattavellai @ Devakar v. State of Tamil Nadu, has established critical guidelines aimed at safeguarding the integrity of deoxyribonucleic acid (DNA) samples in criminal investigations, particularly those involving severe crimes like rape and murder. This ruling was prompted by inadequate handling of DNA evidence, evidenced by significant delays in sending vaginal swabs to Forensic Science Laboratories (FSLs) and the inability to establish a reliable chain of custody.

Key Highlights:

• Case Background: This ruling arose during a serious criminal case involving accusations of rape, murder, robbery, and attempted murder. The Supreme Court found delays in the forensic analysis of DNA samples, raising concerns about contamination.

• Supreme Court Directives:

  • The Director Generals of Police in all states are instructed to create and distribute standardized Chain of Custody Registers and accompanying documentation to ensure uniformity in procedures across investigating authorities.
  • Although “Police” and “Public Order” are under the State List of the Seventh Schedule of the Constitution, the court emphasized the necessity for these guidelines to establish consistency in procedures across states.

• Guidelines Issued by the Court:

  1. Documentation Requirements: Proper collection documentation of DNA samples is mandatory, which should include FIR number, relevant laws, and identity details of the involved personnel.
  2. Responsibilities of the Investigating Officer: The officer must manage the transportation of DNA evidence to the designated police station or hospital within 48 hours, with recorded reasons for any delays.
  3. Sample Preservation: DNA sample packages must remain unopened and sealed pending trial or appeal unless authorized by the trial court.
  4. Chain of Custody Maintenance: A log of the Chain of Custody must be preserved throughout the legal process, and any procedural lapses must be explained by the responsible investigating officer.

• Laws and Precedents Referenced:

  • The Supreme Court previously ruled in Anil v. State of Maharashtra (2014) that DNA profiles are credible, but depend on proper laboratory procedures.
  • In Manoj and Ors. v. State of Madhya Pradesh (2022), DNA evidence was dismissed due to contamination concerns from an open area.
  • Additionally, in Rahul v. State of Delhi, Ministry of Home Affairs (2022), evidence was rejected due to potential tampering during prolonged storage in police custody.

• Conclusion on DNA Evidence: The Supreme Court stipulated that DNA evidence, treated as opinion evidence under Section 45 of the Indian Evidence Act, requires scientific and legal validation, as its probative value may vary by case.

Additional Notes:

• Definition of DNA: Deoxyribonucleic acid encodes genetic information and can be extracted from biological substances such as blood, semen, and saliva. Matching DNA profiles between a crime scene sample and a suspect can indicate a biological relationship but is not solely definitive evidence in court.

• Significance: The ruling emphasizes the vital role of both investigative practices and laboratory protocols in ensuring the integrity and reliability of DNA evidence in criminal cases, directly impacting judicial outcomes.

This summary encapsulates the Supreme Court’s intent to standardize procedures related to DNA evidence collection and handling, thereby enhancing the overall efficacy of criminal justice in India. The ruling underscores the judiciary's proactive approach in addressing practical impediments faced by law enforcement agencies in the accurate attribution of forensic evidence.