But the moment you join our club
I’m pretty militant on anti-doping. But to me this is simple. As a bike racer, I signed my name, explicitly, to an anti-doping policy when I applied for a license. That’s me voluntarily placing myself under the jurisdiction of USADA.
If someone doesn’t sign their name to a contract saying they won’t dope, I don’t think there’s jurisdiction.
There should be no gray area here. That’s the entire point of licensing. To make someone sign their name to a code of conduct - not just for anti-doping, but all the rules of the sport.
Edit: If joining your club included signing on to an anti-doping policy that included submitting to enforcement, then great. If it didn’t, then I don’t know how you can enforce anti-doping.