In this literary source purportedly recounting early episodes of judges, Abū Yūsuf (d. 182/798) issues a clever ruling for ʿAbbāsid Caliph Hārūn al-Rashīd, effectively saving his son – a prince – from an accusation of zinā (fornication or adultery) by operation of the “doubt canon,” which requires legal officials to “avoid criminal punishments in cases of doubt.” The doubt here is a judicial knowledge, rather than established evidence by a confession or witnesses. He is rewarded by being made Chief Judge (qāḍī al-quḍāt) of Baghdad.