To combat aggressive deletion of important footage that the world has the right to see

Essentially the manufacture produces a professional camera for journalist in politically dangerous places that has two storage methods....

An internal Hdd... and a standard tape drive.

If a police ask to delete your tape... just give them your tape.

This is since every time you record, and set the camera to stealth... It records to both the tape and the internal hidden hdd. And without going to a special setting... just deleting the footage from the tape will not remove it from the hidden hdd.

This will ensure BBC will not lose their recording due to arrest by Iranian secret police see link [link]