The physical evidence identification room of the Public Security Bureau is to identify the authenticity of the relevant items involved and provide strong evidence for solving the case. Judicial expertise is conducted by the Bureau of Justice and implemented by the judicial expertise department. Judicial expertise refers to the activities that appraisers use science and technology or specialized knowledge to identify and judge the specialized issues involved in litigation and provide expert opinions. In other words, judicial expertise refers to the activities in which judicial organs or parties entrust legal expertise units to identify and judge the specialized issues in a case by using professional knowledge and technology in accordance with legal procedures.