That's not the case here, and it's irrelevant. When I noticed the discrepancy between my camera's reported speed and my speedometer, I then compared it with a GPS-based speedometer app in my iPhone. The iPhone and car speedometer were in perfect sync. The camera-indicated speed was indeed extremely low, and so low that I have to think it was made deliberately wrong in order to provide misleading information in court, to fight in jurisdictions where such things are overlooked.
Let's say I was in court for some kind of accident, and I was going 70 MPH in a 60 MPH zone. The video recording of the crash shows the camera says 60 MPH, so it never comes up that I'm partially at fault because I was speeding. The other party in the crash is screwed by faulty evidence.