Is it permissible to pray behind an imam who does not pray Witr?

The Witr prayer is a confirmed Sunnah (practice) that the Prophet, peace and blessings be upon him, consistently performed. However, it is not among the obligatory prayers, the omission of which would incur sin, according to the majority of scholars. Praying behind someone who does not perform Witr is valid. The proof for this is that the Prophet, peace and blessings be upon him, said concerning the man who swore that he would only perform the prayers that were obligatory upon him: "He has succeeded if he speaks truthfully."