What set off the investigation was when the Doctor's nurse was stopped entering the US from Canada. Her car was randomly searched, and they found drugs that are still illegal in this country, while legal in Canada. Some of them were "PEDs". That led to an investigation of the doctor and the names of several prominent American athletes were found on his patient lists. There is, as far as I can tell, still no evidence that he prescribed, or gave, anything illegal (in the US) to any of those athletes. Nor is there any evidence that he added anything into the athletes' blood when he re-injected it. Yes, this might be considered blood doping, which is illegal in some sports (someone above mentioned bike racing). But whether it is the exact same thing is still unclear. Later