Prem Sagar Manocha v. State (NCT of Delhi)
Background
The appellant, a Deputy Director at the Rajasthan State Forensic Science Laboratory, had given a forensic opinion in the Jessica Lal murder trial about two fired cartridge cases. At trial he gave a court-prompted answer that the two cartridges appeared to have been fired from different firearms, after earlier saying he could give no definite opinion without the actual weapon. The Delhi High Court, while deciding the appeal against the acquittal of the accused, took suo motu notice under Section 340 CrPC and directed its Registrar General to file a perjury complaint against him under Section 193 IPC, believing his oral testimony contradicted his written report.
Decision Breakdown
The Supreme Court held that the appellant's trial testimony was not actually inconsistent with his written report: in both, he maintained that a truly definite opinion required examining the suspected firearm itself, which was never recovered. His answer about "two different firearms" was a qualified response to a specific court question, not a voluntary reversal of position to favour the accused. The Court reiterated that expert witnesses must be given latitude since their evidence is only advisory, and that mere rejection or an inconclusive opinion does not by itself amount to perjury or justify proceedings under Section 340 CrPC. It noted that this Court's own earlier judgment in the main Jessica Lal appeal had already described this very testimony as "inconclusive" rather than dishonest. Consequently, the High Court's Section 340 proceedings against the appellant were quashed and the appeals allowed.
Lesson Learnt
An expert witness who honestly flags the limits of their opinion (e.g., needing certain physical evidence for a definite conclusion) cannot be prosecuted for perjury merely because their testimony is inconclusive or appears to shift under court questioning: perjury requires actual dishonest or deliberate falsehood, not a cautious, qualified professional opinion.