COURT REVERSES RAPE CONVICTION OVER DNA EVIDENCE

Why in the news?

The Madras High Court overturned a rape conviction due to overreliance on DNA evidence, highlighting its limitations and the need for corroborative evidence in criminal cases.

COURT REVERSES RAPE CONVICTION OVER DNA EVIDENCE - UPSCsource:wikimedia

About DNA Profiling and Its Legal Implications:

  • Court Case and Judgment:
    • Recent Ruling: The Madras High Court overturned a rape conviction, finding that reliance on DNA evidence alone was insufficient.
    • Case Details: The conviction was based on a DNA test showing a 99.999999998% probability of paternity, but the victim later admitted to false accusations.
    • Court’s Findings: The judges concluded that the prosecution failed to prove the case beyond reasonable doubt.
  • DNA Evidence and Its Reliability:
    • How DNA Works: DNA, present in all cells, is used in forensic profiling by examining specific genetic markers called Short Tandem Repeats (STRs).
    • Limitations: DNA profiling is probabilistic, not infallible, and can be compromised by issues like contamination or procedural errors.
    • Forensic Concerns: Issues like sample contamination and procedural flaws can affect the reliability of DNA evidence.
  • Legal Perspective on DNA Evidence:
    • Probative Value: DNA evidence is not conclusive proof of identity; it indicates likelihood based on statistical analysis.
    • Court Precedents: Previous cases highlight that while DNA is valuable for investigations, convictions should not rely solely on DNA without corroborative evidence.
    • Future Outlook: Although DNA accuracy is improving, it cannot yet be deemed infallible; hence, absence of DNA evidence should not be used to infer guilt.
About Deoxyribonucleic Acid(DNA):

  • Discovery: Discovered by Friedrich Miescher in the late 1800s; structure revealed by Watson, Crick, Wilkins, and Franklin in 1953.
  • Structure: Double helix with alternating sugar (deoxyribose) and phosphate backbones; bases adenine (A), cytosine (C), guanine (G), and thymine (T). A=T and C=G.

Types of DNA:

  • A-DNA: Right-handed helix, less common, asymmetric.
  • B-DNA: Right-handed helix, most common form, asymmetric with major and minor grooves.
  • Z-DNA: Left-handed helix, zigzag backbone, found in various organisms.

Functions of DNA:

  • Protein Synthesis:
  • Transcription: DNA to RNA conversion.
  • Translation: RNA to amino acid chains (proteins) by ribosomes.
  • Modification: Proteins are folded and structured for function.

About DNA Profiling Bill:

  • Bill: The DNA Based Technology (Use and Regulation) Bill, 2017, drafted by the Law Commission.
  • Purpose: Regulates human DNA profiling to ensure credibility and restrict misuse.

Institutions:

  • DNA Profiling Board: Regulatory authority fo r accreditation, guidelines, and advising governments.
  • DNA Data Bank: Stores and maintains DNA profiles in five indices: crime scene, suspects, offenders, missing persons, and unknown deceased.