Sanchao yaodian 三朝要典 "Important Canon on Judicial Cases of the Three Reigns" is a collection of documents on three extraordinary legal cases during the Wanli 萬曆 (1573-1619), Taichang 泰昌 (1620) and Tianqi reign-periods 天啟 (1621-1627) of the Ming period 明 (1368-1644).
The three cases are the enforced transferral of Emperor Xizong's 明熹宗 (r. 1620-1627) foster-mother, Chosen Attendant Li 李選侍, to the Huiluan Palace 噦鸞宮 in 1620, while she had insisted to dwell in the Qianqing Palace 乾清宮, which was only allowed to the emperor and his mother (the "Palace-removal case" Yigong an 移宮案); secondly, an alleged attempted murder of the heir apparent Prince Zhu Changluo 朱常洛 arranged by Lady Zheng 鄭貴妃 in 1615 (the "Club-hit case" Tingji an 梃擊案); and thirdly, the "Red-Pill case" Hongwan an 紅丸案 that dealt with the death of Emperor Guangzong 明光宗 (r. 1620) after only one month of reign (the former Prince Zhu Changluo), caused by a pill given to him by Li Kezhuo 李可灼, probably on the order of Lady Zheng.
The collection is 24-juan long and was compiled on imperial order under the supervision of Gu Bingqian 顧秉謙 (1550-?), Huang Liji 黃立極 (1568-1637) and Feng Quan 馮銓 (1595-1672). The text was finished in 1626.
It includes documents that demonstrate how the powerful chief eunuch Wei Zhongxian 魏忠賢 distorted the law to blackmail and eliminate his opponents of the Donglin Faction (Donglin dang 東林黨) of courtiers.
The original book was destroyed when the Chongzhen Emperor 崇禎 (r. 1627-1644) purged Wei Zhongxian and his whole clique, and only a very small amout of copies have survived, one original of the Sutra Printing Shop (called jingchangben 經廠本) in 20 volumes in the library of the Chinese Academy of Sciences (Zhongguo Kexue Yuan 中國科學院), the same edition in 12 volumes in the Beijing Library (Beijing Tushuguan 北京圖書館), a reprint from 1626 in 12 volumes owned by the Beijing Library, and a manuscript copy by the Kanyunyidi Studio 看雲憶弟居, in 6 volumes, today owned by the Archaeological Department of the Chinese Academy of Social Sciences 中國社會科學院考古學研究所.