Cooperation among nodes is vital in Mobil Ac Hoc Networks (MANETs) since in such networks nodes depend on each other for forwarding and routing packets. However, cooperation in such operations consumes nodes' recourses such as battery and bandwidth. Therefore it is necessary to design incentive mechanisms to enforce nodes to forward packets when the source and destination of the packet are other nodes. In this paper, we present a distributed fair solution to judge, punish and re-admit a selfish node, forcing nodes to cooperate with each other. Our scheme is different from previous ones in that it combines two characteristics that have been separately handled in previous works. The first characteristic is fairness of reputation system regarding position of nodes in the network and the second one is the ability to cope with false reputation information distributed by malicious nodes. Unlike previous fair solutions, this scheme can cope with false disseminated information. We propose a new scheme to manage both trust and reputation based on global information, considering the fact that it is to be designed for a fair reputation system. The experimental results suggest that the proposed scheme can successfully identify selfish and malicious nodes and react accordingly.