Community decisions about access control in virtual communities are non-monotonic in nature. This means that they cannot be expressed in current, monotonic trust management languages such as the family of Role Based Trust Management languages (RT). To solve this problem we propose RT , which adds a restricted form of negation to the standard RT language, thus admitting a controlled form of non-monotonicity. The semantics of RT is discussed and presented in terms of the well-founded semantics for Logic Programs. Finally we discuss how chain discovery can be accomplished for RT . Key words: Distributed Trust Management (DTM), Virtual Communities (VC), Peer to Peer (P2P), Role Based Trust Management (RT), Non-monotonic Policies, Chain Discovery.