Litigation between Marquis Wei and Yuan Xuan and the Marquis' Defeat and Arrest

In 632 BC, after the Battle of Chengpu, Marquis Cheng of Wei was accused by his minister Yuan Xuan before Duke Wen of Jin, the newly established hegemon. The conflict stemmed from the Marquis's shifting allegiance between Jin and Chu, and his execution of Yuan Xuan's son, Yuan Jiao, while Yuan Xuan was on a diplomatic mission. Duke Wen convened a formal tribunal to hear the case. The Marquis appointed Ning Wuzi as his advocate, Shi Rong as the judge, and Zhen Zhuangzi as the defendant's seat. After proceedings, Duke Wen ruled against the Marquis of Wei. Enraged by the defeat, the Marquis ordered Shi Rong executed and Zhen Zhuangzi's feet cut off, but spared Ning Wuzi for his loyalty. Duke Wen then arrested the Marquis and delivered him to the Zhou capital, where he was imprisoned in a deep chamber. This case stands as a landmark example of hegemonic judicial authority over a ruling lord.

Marquis of Wei lost the case. He was arrested by Duke Wen, sent to the royal capital of Zhou, and imprisoned. His judicial officer Shi Rong was executed, and his representative Zhen Zhuangzi was subjected to foot amputation on the Marquis's own vengeful orders after the verdict.

Whether the Marquis of Wei violated feudal obligations by killing Yuan Xuan’s son and betraying his alliance with Jin, and whether the hegemon had legitimate jurisdiction to adjudicate a dispute between a vassal ruler and his minister.

The trial demonstrated that the hegemon could legitimately exercise supreme judicial power over feudal lords, challenging the Zhou king's nominal monopoly on justice. It strengthened Duke Wen's hegemony, set a precedent for resolving inter-state and lord-minister conflicts through arbitration, and highlighted the tension between ritual propriety and emergent legal practices in the Spring and Autumn period.