In some implementations, an internet protocol multimedia subsystem (IMS) may receive a device identity of the user device as part of an emergency call. The IMS may transmit the device identity to an emergency call server (ECS). The IMS may receive, from the ECS, a subscriber identity of the user device. The IMS may transmit the subscriber identity to a public safety answering point (PSAP) through a next generation core services (NGCS) network that uses a Stir and Shaken protocol. The emergency call is then established with a true subscriber identity of the user device.