In this historical text, Muḥammad b. Yūsuf al-Kindī reports that the Qaysī Arabs and Yamanī Arabs, two warring tribes, were prohibited from testifying against one another by the Egyptian judge Tawba b. Namir (115–120/733–738). Ahmed El Shamsy references this source to explore how the concern of bias due to enmity might also serve as sufficient grounds to reject testimony in an internal Muslim context, if there are factional tensions.
On the second page, al-Kindī discusses the issue of non-Muslim testimony. He writes that while many Muslim jurists barred non-Muslim testimony entirely, those authorities who permitted it were faced with the challenge of devising techniques to screen witnesses from diverse communities. In this regard, Al-Kindī records how the Egyptian ḥadīth scholar and judge Khayr b. Nuʿaym (in office 120–27/738–45) verified the personal credentials of non-Muslim witnesses by interviewing members of their respective circles (yasʾal ʿan ʿadālatihim fī ahl dīnihim). This procedure assumed that non-Muslims might also obtain a status of righteousness, a notion which is not necessarily assumed by other jurists.
Read the text (in Arabic).