A typical red light camera intersection has cameras positioned at a corner of an intersection, on poles a few yards high. The video and photo cameras point towards oncoming traffic so the cameras can photograph or video cars driving through the intersection. Red light systems do not necessarily have cameras at all four corners of an intersection. Some intersections also have cameras to capture traffic photos from the rear as well.
False positives are typically prevented during traffic congestion by having minimum speed limits for a violation to occur. In some states, a ticket is issued to the car's registered owner, no matter who's actually driving. However, a police office typically has to compare traits of the license plate with the registered owner like. You are a male or a female or a certain age group or even race.
In some states red light camera tickets only needs to photograph the car from behind, since the authorities only need a clear view of the rear license plate. In other states, the actual driver is responsible for paying the ticket and must be verified. If you were not the driver of the car often times you will be threatened to turning in the driver which is referred to as a snitch ticket. In this case, the photo enforced system needs a second camera in front of the car, in order to get a shot of the driver's face. The ticket is still sent to the car's owner after verification.