Abstract: A method for identifying non-terrorists among a plurality of participants and/or potential participants using a communication system includes electronically communicating a verification request from a first participant to a second participant, wherein the second participant is a member of a personal network of the first participant, and electronically communicating a verification request from the second participant to a third participant, wherein the third participant is a member of a personal network of the second participant. The method also includes receiving replies to the verification requests sent by the first and second participants, and determining a likelihood that the first participant is a non-terrorist threat based on the replies received from the second and third participants.