The Criminal Procedure Law promulgated in 1979 established the proof structure of segmental responsibility and selective relay in China. It is reflected not only in the relationship between investigation, prosecution, and trial, but also in the relationship between upper and lower trials. In this structure, the public security organs, the People's Procuratorate, and the People's Court have differences only in the investigation procedures and methods in their respective dominant litigation stages, not in the investigation responsibilities and objectives. The backend case handling agency has the responsibility to continue investigating. The subject of the relay has the right to choose whether to continue the investigation according to the legal proof standard, as well as the discretion to choose the main body, scope and methods to continue the investigation. Although the Criminal Procedure Law has undergone several revisions, it has moved towards optimizing its structure. The structure of China's criminal proof system have the following distinctive characteristics: first, the decentralization of fact-finding powers; second, the uniformity of the investigation responsibilities of specialized agencies; third, the power of unit determination of the scope of investigation; fourth, the evolution of “investigating” the fact into “following up” the truth; and fifth, the defense side as an aid in finding the truth.