The Prophet ﷺ appointed Ibn Umm Maktum to lead the people in prayer, and he was blind.
أن النبي ﷺ استخلف ابن أم مكتوم يؤم الناس وهو أعمى.
Abu Dawud (595) narrated it from Muhammad bin Abdul-Rahman Anbari Abu Abdullah, who said, Ibn Mahdi narrated to us, Imran Qattan narrated to us, from Qatada, from Anas, and he mentioned it. Its isnad is hasan, for Imran Qattan, who is Ibn Dawar (with a fatha on the waw, followed by a ra), Abu Awwam Qattan, is a subject of disagreement. Abu Dawud and Nasai declared him daif, while Ibn Hibban mentioned him in Thiqat. Bukhari and Tirmidhi said he was truthful, and Ibn Adi said, he is among those whose hadith is written down.This hadith was also narrated by Imam Ahmad (12344), Abu Yaala (3098), and Bayhaqi (3/88), all of them through the route of Ibn Mahdi, with the same wording, and they added the statement of Anas, "I indeed saw him on the day of Qadisiyyah, carrying a black banner."This appointment as deputy was only for the prayer, as Abu Dawud mentioned, and likewise Imam Ahmad (1300) mentioned it from Bahz, from Abu Awwam Qattan, with the same wording (1300).Khattabi said in his Maalim, "The Prophet ﷺ only put him in charge of the prayer, not of judicial matters and rulings, for a blind man is not permitted to judge among people, since he cannot perceive people's identities, cannot verify their persons, and does not know for whom or against whom he is ruling, and he must rely on the testimony of others in everything connected to these matters. And ruling based on relying on others' testimony alone is not permissible." End of quote.A useful note, a group of scholars narrated that the Prophet ﷺ appointed Ibn Umm Maktum as his deputy thirteen times.