Because the US government doesn't think you know how to drive in reverse.
Apparently backup cameras save lives. Lots of them. So many in fact that the US Department of Transportation (DOT) has just announced new safety standards that will require all automakers to have those cameras in every new car by 2018. According to the National Highway Traffic Safety Administration (NHTSA), an estimated 200 lives per year are saved because of backup camera. All told, there are around 210 fatalities and 15,000 injuries per year caused by back-overs.
Children under the age of five account for 31 percent of those fatalities. Adults over age 70 account for 26 percent. Specifically, automakers will have to install a backup camera that will allow drivers to see a 10-foot by 20-foot zone behind the car. So how much will this cost automakers, exactly? The NHTSA estimates a camera and display screen will run between $132 and $142 per vehicle for model year 2018. So why all of a sudden has the DOT made this a rule? It all started when the department was sued by two individuals who lost children in back-up accidents. It wasn't long before consumer rights and safety groups started getting involved.
Obviously back-up cameras will save lives, but what's equally important is for drivers to always look out the rear- and side-view mirrors first before going in reverse (or selecting any gear, for that matter). Simply paying attention is always the best deterrent.