A controller in a communication system for controlling communications with a group of associated subscriber units and method thereof, where the controller includes a receiver operable to receive a request for a subscriber unit to communicate with the group of associated subscriber units (703); and a processor coupled to the receiver and operable as a comparator to provide a comparison of a first association constraint corresponding to the subscriber unit and a second association constraint corresponding to the group (709); and a decision function that allows, only when the comparison is favorable, communications between the subscriber unit and any other subscribers of the group of associated subscribers that also have such communications allowed or enabled (717).