Abstract: A method and system for determining whether at least one telephone subscriber participating in a communication session is marked for monitoring by a Law Enforcement Agency (LEA) and, if so, for automatically marking for monitoring all remaining participants in the communication session. In a presently preferred exemplary embodiment, the subscribers are marked for monitoring their communications for a selected period of time by a starting the timer each time a new subscriber is marked. In another preferred exemplary embodiment, the subscribers marking level is detected and verified to determine if the marking level satisfies a pre-defined condition associated therewith. If so, the corresponding subscriber is marked for monitoring and the subscriber's subsequent communications are monitored.