>> if you can get suspended for being stupid, this was stupid. >> reporter: ray paulick is a veteran horse racing expert. >> you don't mess with the franchise. the derby is such a big deal to churchill downs. they really can't afford to have this tarnished. >> reporter: in a statement tonight, churchill downs cited baffert's prior history of failed drug tests saying, "reckless practices and substance violations that jeopardize the safety of our equine and human athletes, or compromise the integrity of the sport, are not acceptable." this move comes after baffert's horses had five medical violations over the past year alone. >> when they're testing at these levels, it's ridiculous. >> reporter: tonight, baffert is also banned from racing in new york state indefinitely. baffert's attorney confirms the second sample was positive, but he maintains that the amount in the bloodstream is too small to have given the horse an advantage to win. but any amount is banned on race day in kentucky. david begnaud, cbs news, los angeles.