They take pictures of both in many places. One to catch the car's plate, the other to identify the driver so you can't weasel out of the ticket. Not that I think red light cameras are anything but wrong-headed and unsafe, as I've previously posted (with evidence for that position).
Outfitting more of our lights with the reverse indications that allow police officers to successfully ticket red light runners and having officers actually ticket for such dangerous behavior rather than focusing primarily on speed enforcement would probably cut down significantly on red light running. Officers are capable of making an on the spot decision as to whether a minor red light infraction was in fact the safest course of action, as it sometimes is.
We also need to fix the lights that don't have any all red interval. That's also unsafe.
Quote from an article about Houston's red-light cameras:
"Citations sent to motorists will include three photographs. One photograph will show the vehicle, another will show the license plate number and another will show the vehicle in the intersection while the light is red.
The cameras will not take a photograph of the driver."
Quote from an article about the red light system in Everett Washington:
"
Because the cameras cannot legally take images of a driver's face, violations are treated similarly to parking tickets, not moving violations that are placed on a driver's record. The ticket will be mailed to a car's registered owner after the video is reviewed by the company and an Everett police officer."
Quote from an article about Illinois red-light cameras:
"Illinois law prohibits red-light cameras from capturing images of a driver’s face, which is why all cameras in the state capture only pictures and video of a vehicle’s rear."
I think it's safe to say that most systems do NOT take photos of the driver. In part this is to avoid challenges based on privacy concerns. And this is why the tickets do not count against your driving record or insurance. They are treated the same as a parking ticket. The owner of the vehicle is responsible, not matter who is driving.