Right action when being lied to If a family member has been dishonest with me, and upon discussing the issue denies the lie, what is the best action?
Everything that happens to us is caused by an action we have committed in the sansara. This was common to Buddha as well (Devdatta's actions etc.).
Therefore the answer to the question What is the best action? is,
Understand that this is a result of an action you have committed in the past (maybe in previous births). Further, try to spread metta (kindness, love) towards him though he is lying to you. In future, he will admit what he did today. Until that there's no much meaningful thing to do.