Abstract: The process of the mutual accusations in the Su case in 1727 was reconstructed in great detail．The mediation and the judicial process in which county school heads and sub-magistrates played a role in handling cases and that prefects rejected appeals，were very evident．The Su case indicated that many factors restricted mediation, that the judicial system in the basic level on the book was different from its practice, and that judges' legal knowledge greatly impacted on their final judgments．