MIAMI — Paul Schippereit was crossing Biscayne Boulevard at 23rd Street when a yellow BMW 320i slammed into him and changed the trajectory of his life. The young Miami police officer was responding to a robbery. The victim had been shot in the face. The year was 1984. Only 27 and a sworn officer for two years, Schippereit would spend the next four years in and out of hospitals and undergoing surgeries in a futile attempt to recover from a badly broken leg, internal bleeding and a severe brain injury. He was placed on permanent disability in 1988 and never returned to work. Schippereit’s watch …