Anyone who thinks inward facing cameras, whether in a locomotive, bus, truck, airpane etc., have any practicality for the prevention of accidents and/or assessing discipline is right out in lala land because too much data (in the form of videos) will be produced, and somebody [else] will have to watch those videos. This implies that for each person running a train/bus/truck etc.,there would have to be another one watching, and watching his/her monitor without looking away or going on potty breaks. Unless, of course, you want the US to turn into the former East Germany, where half the population was spying on the other half. I didn't spend a year in Vietnam for that sort of thing to come to pass here in this country. Read George Orwell's 1984.