Pingyuanlu 平冤錄 "Records of balancing unfair verdicts" is a collection of law cases compiled by Zhao Yizhai 趙逸齋 (or Zhao Yiqi 趙逸齊, late 13th cent.) and later commented by Wu Zi 吳鼒 (1755-1821). The short text quotes mainly from the Song-period 宋 (960-1279) book Xiyuanlu 洗冤錄 and explains how to examine corpses to find out the factual circumstances of death. It includes 43 cases that help discerning between different types of injuries and various manners of death, from methods of suicide to hanging, beating, poisoning, freezing, injuries by scalding, or bodies damaged by animals eating from them. The author of the Pingyuanlu added some new findings to the quotations from older texts.
The oldest print was produced during the Ming period 明 (1368-1644) by Wang Shenwu 王慎吾. It is part of Wu Zi's collection Song-Yuan jianyan sanlu 宋元檢驗三錄 from 1812.