A simple way would be for the camera to have secret built in bluetooth. Even if the camera were set up hard wired to a private intra-net the image could be retrieved if an external bluetooth receiver was positioned in range of the camera.

For example a car could be parked with a receiver/recorder outside an embassy, or a tourist could have a receiver/recorder in their purse while touring inside the Capital building.

(and that is just one way to do it)