Grave sins

Praying behind an Imam who Commits Sin.

As-Salam-O-AlykumThere was one house just adjacent to the masjid, where one poor family was living since about 90 years. Now one Moulvi came to this place and just instigated the people to extend the mosque by taking the house of that poor person. Moulvi told the people to give the house to this poor person in some illegal place without proper property documents etc. Hence the poor person has shifted his house to illegal place thinking that if he can help the people in extending the mosque then it is good and he will also get Sawab-E-Jariya.Now the Moulvi played the game, he built his own house there only where the poor person was staying and not only that he also occupied the space of masjid (4 Feet) in his house. That means the Moulvi has cheated the poor person by telling that they are building the mosque hence he should give the house for this noble cause and after vacating the house by poor person, the Moulvi occupied this land as well as the land of masjid (4 feet) and built his own house there.The person who destroy the mosque (MOULVI) for his personal benefits, should he not be treated as KAFIR or MUNKIR and the prayer under his Immamat is Jayes or legal.In this situation and in light of the Islamic Shariyat, can the people should pray behind him under the leadership of his Immamat and can the MOULVI now eligible to do the Immamat.Can you please express your valuable views on this point so as to come to some conclusion and to stop such illegal things committed by MOULVIS.