This project was an experiment in testing boundaries. The large format camera is set on a tripod, pointing out the back window of of a car. The lens is focused on a fixed point, three metres behind the car. A shutter release cable is ran through to the front of the car.
As both the driver of the vehicle and the photographer, there are strict rules to attempting to take a shot. Firstly, the car has to be stuck in traffic so heavy that nothing is moving. This is to allow enough time to apply the hand brake and completely switch off the engine. As well as for vehicle safety, this negates vibrations from the engine that would otherwise shake the camera. At this time, without adjusting the camera, I simply operate the shutter release then start the vehicle engine and am ready to continue being stuck in traffic.
For me there are two distinct areas of legal or ethical concern; vehicle safety and invasion of privacy. If the traffic is not moving and the handbrake of the vehicle is engaged, the only issue would be when the engine is switched off the emergency hazard lights should be engaged, however, as the engine is only off for the time it takes to take a photograph, perhaps five to eight seconds, this seems to be a nominal risk.
The second question is a little more vague; If I do manage to capture any kind of portrait of whoever is in the vehicle behind me, is that an invasion of privacy?