GS 2 POLITY
Context
The Supreme Court of India, in the case Kataraulla @ Devrat v. State of Tamil Nadu, has issued guidelines to safeguard the integrity of DNA evidence in criminal investigations.
The directions focus on preventing sample contamination, ensuring proper documentation, and maintaining a clear chain of custody, especially in sensitive cases like rape and murder.
Why These Guidelines Were Needed
- Case Background:
- The case involved rape, murder, and robbery, where unexplained delays occurred in sending samples to the Forensic Science Laboratory (FSL).
- The chain of custody could not be established, raising concerns about sample contamination and reliability.
- The Supreme Court emphasized that contaminated evidence cannot be ruled out, making convictions questionable.
- Past Concerns:
- Similar issues have been raised earlier, including Rashid v. State of Delhi and Ministry of Home Affairs v. DNA Evidence Case (2022), where samples were kept for months without examination, raising doubts about tampering.
Supreme Court Directives
The court laid down clear step-by-step protocols for handling DNA evidence:
- Collection and Documentation
- Prepare a Chain of Custody Register at the investigation stage.
- Record details of every person handling the sample — investigating officer, police station, FSL, etc.
- Register must be submitted to the trial court.
- Packaging and Transport
- Use tamper-proof containers with labels and signatures.
- Samples must be sent to FSL within 40 hours of collection.
- Investigating officer responsible for timely transportation.
- Proper Authorization
- If samples need to be stored or moved, court approval is mandatory.
- No sample should be transferred without legal documentation.
- Ensuring Quality Control at FSL
- Experts must verify purity and integrity before testing.
- Delay without valid reasons must be reported to the court.
Importance of DNA Evidence
- DNA is a biological blueprint carrying unique genetic information.
- It can be extracted from blood, semen, saliva, hair, bones, etc.
- In criminal cases, DNA helps:
- Identify suspects and link them to crimes.
- Exonerate innocent individuals.
- Establish biological relationships.
However, DNA alone may not be enough to convict; it must be supported by corroborative evidence.
Significance of the Judgment
- Strengthens Forensic Standards: Enhances reliability of DNA evidence in courts.
- Prevents Wrongful Convictions: Ensures no innocent person is convicted due to mishandling of samples.
- Accountability: Holds investigating officers responsible for timely and proper handling of evidence.
- Judicial Oversight: Makes the trial court a key checkpoint in the evidence chain.