During his Caliphate, ʿAlī b. Abī Ṭālib – Allah be pleased with him – saw some armor of his with a Christian. He decided to take the matter up legally, so he took the dispute to Shurayḥ (the Judge).
ʿAlī said, “This is my armor, and I have not sold it nor given it away.” Shurayḥ said to the Christian, “What have you to say about what the Amīr of the Believers claims?” The Christian replied, “It is my armor, although I do not regard the Amīr of the Believers to be a liar.” Shurayḥ then turned to ʿAlī, “O Amīr of the Believers, do you have any proof (of ownership)?” ʿAlī laughed and said, “Shurayḥ is correct, I have no proof.” So Shurayḥ judged that the armor was the Christian’s. The Christian took it and began to walk away but then returned. He proclaimed, “As for me, I testify that this is the judgment of the Prophets – the Amīr of the Believers himself takes me to his judge and the judge rules against him! I bear witness that there is no deity deserving worship but Allāh and I bear witness that Muḥammad is the Messenger of Allāh. By Allāh, the armor is yours o Amīr of the Believers. I followed the army when you were on your way to the Battle of Ṣiffīn and the armor came out of your equipment.” ‘Alī said, “If you have accepted Islām the armor is yours.” And then he put him on his horse. Al-Shaʿbī (the reporter of this incident) said, “I was later informed by those who saw this man that he fought the Khawārij (alongside ʿAlī) at the battle of Nahrawān.”
Ibn Kathīr, Al-Bidāyah wa Al-Nihāyah Vol.8 p5.