145th Kentucky Derby: Horse deaths threaten sport's future

On Saturday, all eyes will turn to thoroughbred racing for the 145th running of the Kentucky Derby. But a dark cloud is hovering over the sport, as horse racing’s biggest story has nothing to do with racing itself.

On Saturday, all eyes will turn to thoroughbred racing for the 145th running of the Kentucky Derby. But a dark cloud is hovering over the sport, as horse racing’s biggest story has nothing to do with racing itself.