As far as I understand, the solution is checked for the presence of phenolphthalein powder (which is applied to the currency notes during trap proceedings) and not for the pH value of the solution. Colour of the solution is a visual indicator of the presence of the phenolphthalein powder.
It is the Investigating Officer who is recognized in the Criminal Procedure Code for the purposes of the investigation. He can take all necessary steps for the investigation. As regards someone else signing for the SP, you have to make enquiries with the concerned organisation itself as to what is contained in their guidelines.
Check from the concerned forensic science laboratory concerned, as to who is authorized to sign while receiving samples. These are procedural matters within an organisation, which can be replied to by that organisation itself, and these are not questions of law which this forum can entertain.
Your question No. 4 is again a procedural question to be answered by the organisation concerned itself. There is no specific law in this regard.
Case diary is a privileged document under law. An accused is not entitled to ask for its copies.
Your questions Nos. 5 and 6 again would have to be answered by the investigation agency itself, if they have any internal guidelines in this regard.
Dr. Ashok Dhamija is a New Delhi based Supreme Court Advocate and author of law books. Read more about him by clicking here. List of his Forum Replies. List of his other articles. List of his Quora Answers. List of his YouTube Videos.
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