Legal basis: Provisions on Several Issues Concerning the Procedures of Drug Extraction, Seizure, Weighing, Sampling and Inspection in Handling Drug Crime Cases Article 22 When taking samples at the scene of drug seizure or the place where the public security organ handles the case, the criminal suspect and witness shall be present, and a sampling record shall be made. Before sampling the packaged drugs, they should be unpacked in the presence of criminal suspects and witnesses, and recorded in the sampling records. The sampling record shall be signed by the sampling personnel, criminal suspects and witnesses. If the criminal suspect refuses to sign, it shall be indicated in the sampling record. When necessary, the investigators shall take photos or videos of the main process of unpacking sampling.