Praying behind ibaadis and innovators
Question

                What is your opinion on the Ibaadi sect? Is it true that Ibn Baaz (may Allaah have mercy on him) described this sect as kaafirs? Here in our mosque in America there are different groups such as Zaydis and Shi’ah. Can we allow any of them to lead the prayers and we pray behind him, or should only Sunnis lead the prayers?.
Praise be to Allah.The Ibaadis are one of the misguided groups, as it says in the Fatwa of the 
    Standing Committee, no. 6935, which says: 
Question: Is the Ibaadi sect regarded as one of the misguided sects of the 
    Khaarijis, and is it permissible to pray behind them? 
The Committee answered as follows: 
The Ibaadis are one of the misguided sects because of their aggression and 
    rebellion against ‘Uthmaan ibn ‘Affaan and ‘Ali (may Allaah be pleased with them both), and it is not permissible to pray behind them. 
And Allaah is the Source of strength. 
Standing Committee for Academic Research and Issuing Fatwas. 
For more information on the Ibaadis please see question no. (11529) 
We cannot find any statement by Shaykh Ibn Baaz to the effect that this group are kaafirs. 
See the ruling on praying behind a Shi’i in the answer to question no.
    20093. 
It is not permissible to allow the followers of innovation that constitutes kufr 
    to lead the prayers, because prayers offered behind them are not valid according to a number of scholars, and because they deserve to be forsaken 
    and rebuked, not put forward for positions of leadership, and because allowing them to lead the prayer may lead to the ignorant being deceived by 
    them. 
Innovations that constitute kufr include such things as saying that the Qur’aan is 
    created, denying that the believers will see their Lord in Paradise, saying that those who commit major sins are kaafirs or will abide in Hell for 
    eternity, denouncing Abu Bakr and ‘Umar (may Allaah be pleased with them) as kaafirs, saying that the Qur’aan has been altered, claiming that the 
    imams have knowledge of the unseen, seeking the help of the dead, and other forms of kufr and shirk. 
This is contrast to one who follows an innovation that does not constitute kufr; prayer 
    offered behind such a person is valid. 
The following question was mentioned in Fataawa al-Lajnah al-Daa’imah 
    (7/364): 
Is it permissible to pray behind an imam who follows innovation? 
The Committee replied: 
Whoever can find an imam who does not follow innovation, let him pray behind him 
    and not the one who follows innovation. Whoever cannot find anyone but the one who follows innovation, let him advise him in the hope that he will 
    give up the bid’ah (innovation). If he does not accept that and his innovation involves shirk – such as one who seeks the help of the dead or 
    prays to them instead of Allaah or offers sacrifices to them – then you should not pray behind him because he is a kaafir and his prayer is 
    invalid, and it is not proper to make him an imam. If his bid’ah does not constitute kufr, such as speaking the intention out loud, then his 
    prayer and the prayer of those who pray behind him is still valid. 
And Allaah is the Source of strength. 
Standing Committee for Academic Research and Issuing Fatwas. 
And Allaah knows best.