A suspect arrested after a shooting refuses to wash his hands. Within what period should GSR sampling ideally be completed for reliable detection?
- A Within 24 hours of firing
- B Within 48 hours of firing
- C Within about 6 hours of firing ✓
- D Within 15 minutes of firing only
Correct answer: C. Within about 6 hours of firing
Explanation
GSR particles are shed rapidly from skin and clothing by ordinary activity, and standard teaching places the practical detection window at up to about 6 hours provided the hands have not been washed. The 15 minute option is far too restrictive, since particles persist well beyond immediate contact, while 24 to 48 hours overstates persistence because routine hand movements remove nearly all residue long before then.
Reference: Parikh's Textbook of Medical Jurisprudence, Forensic Medicine and Toxicology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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