Question: What is the ruling on performing Salaah behind some one who watches TV or is sinful in any way?
Answer: It is Makruh to perform salaat behind one who sees TV or movies as such a person is a fasiq (transgressor).
He should be approached in privacy by a respected figure in the community and be asked to repent and stay away from all such sins.
Fatāwā Dārul Ulūm Zakariyyā, Vol. 2, Pg. 264-265