A license detector system enables a person such as a police officer to monitor vehicles on the road to ensure drivers have valid licenses. Within each valid license is an RFID tag which contains specific information and each RFID tag is able to send that information to a detector when requested. To use the system, the police officer aims the detector at a vehicle, initiates the signal to be received by the RFID tag within the license and waits to receive a signal back from the RFID tag. If a signal is received, then a valid license has been detected within the vehicle. However, if no signal or an invalid signal is received by the detector, then no one, specifically the driver of the car, has a valid license. Upon discovering such information, the police officer should be justified in stopping the vehicle and taking the necessary police action.