Police brutality is now a real issue in the USA. The police kill on average 3 of its own citizens every day. Rarely is an officer charged with an offense, in this instance the officer is caught on film shooting  an unarmed man 8 times in the back as he runs away. He dies at the scene and the officer is later charged with murder which is highly unusual. One can only presume its because this video has become part of the public record and its just too damning for the authorities to ignore and maintain some sort of acceptable image to the general public. The man was pulled over for having a faulty tail light.