They tried traffic cameras here in CA. The cameras were operated by a private company.
The cameras were taking pics of cars in the intersection as soon as the lights turned red. But the cars entered the intersection when the lights were yellow. After many complaints The courts ruled against traffic cameras and they were removed from intersections
The camera company got paid for each Red Light ticket pic they took and it was found out that there was no time allowed for yellow lights. The more Red Light ticket pics the more $ the camera company made. The Courts ruled against this type of ticketing
Also the private camera company got paid a fee for every speeding ticket picture.
The camera company was setting up speed picture traps everywhere and people were getting speeding tickets for going 2 - 3 MPH over the speed limit. The camera company was using unmarked speed traps. Employees were setting up these traps using their private cars and would get paid a % for every speeding pic they took. So they were taking pic of cars going 2 -3 MPH over the speed limit just so that employee could get a bigger pay check. The courts found this out and ruled against this type of ticketing.