Forensic science lab hyderabad

Hi sir/madam What is the procedure to send a forged document along with the admitted document's to send it to forensic science lab Hyderabad by the investigation officer ,my query is whether the io can send only document with out the specimen signature of the witness? Am in doubt that the accused may manipulate the io as they are politically strong and influential. Kindly suggest what can I do to avoid manipulation and send the document's safely to cfsl Hyderabad, also the JFCM refused to send citing 311A that it can send only in case of accused and not the petitioners.