I think in pro sport you should just go off the assumption that someone accused by a neutral (not by a competitor) of doping/match fixing is guilty and wait for them to prove otherwise. It saves years of denial and speeds up the process, otherwise we'll have cases like Lance Armstrong and Floyd Landis, which in the long run harms the credibility of a sport. Cricket for example is lightning quick at investigating things like this and unlike cycling its still considered credible, even when Pakistan play.