Question: Can one who has made Tayammum lead in prayer people who have made Wudhu?
Answer: Praise be to Allah. Imam Ibn Hazm, may Allah have mercy on him, said:
It is permissible for one who has made Tayammum to lead in prayer people who have made Wudhu, and it is permissible for one who has made Wudhu to lead in prayer people who have made Tayammum. It is permissible for one who has wiped over his socks to lead those who have washed their feet and for one who has washed his feet to lead people who have wiped over their socks, because each of the above mentioned people have done what they are obligated to do.
None of them is more taahir (pure) than the other, and none of them is more complete in prayer than the other. The Messenger of Allah (peace and blessing be upon him) commanded that the prayer should be led by the one who has the most knowledge of the Qur'an. He (peace and blessing be upon him) did not specify anything other than that. If there had been any obligation other than that which he mentioned, he would have explained it and would not have neglected it - Allah forbid. This is the view of Imam Abu Haneefah, Abu Yousef, Zufar, Sufyaan, al-Shaafa'i, Dawood, Ahmad, Ishaaq and Abu Thawr. It was narrated on the authority of Ibn 'Abbaas, ,Ammaar ibn Yaasir and a group of the Sahaabah (i.e. Companions) (may Allah be pleased with them). It is also the view of Sa'eed ibn al-Musayyib, aI-Hasan, Ataa', al-Zuhri and Hammaad ibn Abi Sulaymaan, may Allah have mercy on them all.
Imam Ibn Hazm, may Allah have mercy on him, said: 'There is no evidence in the Qur'an or Sunnah, for disallowing that (i.e. to disallow one who has made Tayammum to lead in prayer one who has made Wudhu) or regarding it something unpraiseworthy.