Legal analysis: the scene map and the record of the scene investigation shall be signed by the traffic police, the parties concerned or the witnesses involved in the investigation. If a party or witness refuses to sign or is unable to sign without a witness, it shall be recorded.

Legal basis: Criminal Procedure Law of People's Republic of China (PRC).

Article 50 All materials that can prove the facts of a case are evidence. Evidence includes: (1) physical evidence; (2) Documentary evidence; (3) Testimony of witnesses; (4) the victim's statement; (5) confessions and excuses of criminal suspects and defendants; (6) Appraisal opinions; (7) Records of inquests, inspections, appraisals, investigations and experiments; (8) Audio-visual materials and electronic data. The evidence must be verified before it can be used as the basis for finalizing the case.

Article 128 Investigators shall conduct an inquest or inspection of places, articles, persons and corpses related to crimes. When necessary, people with specialized knowledge may be appointed or hired to conduct inquests and inspections under the auspices of investigators.

Article 129 Any unit or individual has the obligation to protect the crime scene and immediately notify the public security organ to send personnel to conduct an inquest.

Article 130 When conducting an inquest or inspection, investigators must hold the certification documents of the people's procuratorate or the public security organ.

Article 133 An inquest or inspection shall be written in a written record, which shall be signed or sealed by the participants and witnesses.