I believe in states where they are considered constitutional it's because they don't actually give you a moving violation as if a cop saw you run a red light. Instead they give you the legal equivalent of a parking ticket. They don't care who was driving your car, if it is parked illegally they can fine you because you are ultimately responsible for the car. They don't claim you parked illegally, they simply claim your car, for which you are responsible, was in the wrong place at the wrong time.

With the red light cameras, the same principle applies. It's your car, in the wrong place at the wrong time. You pay a fine but it is not considered a moving violation and no points go on your license.

This is how they get around the constitutionality thing.

A different division of the company I work for makes the flippin' things, so I guess if they help my stock go up, they're, um, a good thing.