When performance-enhancing drugs are used every day by the average person–and that will happen–it won’t be possible to hold athletes accountable anymore. A section from a provocative post by Julian Savulescu at Practical Ethics which was inspired by runner Tyson Gay’s recent failed drug tests

“We reached the limits of human performance in sprinting about 20 years ago. To keep improving, to keep beating records, to continue to train at the peak of fitness, to recover from the injury that training inflicts, we need enhanced physiology. Spectators want faster times and broken records, so do athletes. We have exhausted the human potential.

Is it wrong to aim for zero tolerance and performances which are within natural human limits? No, but it is not enforceable.

The strongest argument against doping is safety. The harm inflicted on East German athletes must never be repeated. But anything is dangerous if taken to excess. Water will kill you if you drink enough. As sport has shown over last 20 years, performance enhancers can be administered safely. They could be administered yet more safely if it was brought out into the open.

Of course there is no such thing as risk-free sport. But we need a balance between safety, enforceability, and spectacle. Elite sport itself is fundamentally unsafe, as Team Sky’s Edvald Boassen Hagen and Geraint Thomas, both nursing fractures from recent cycling crashes can tell you. It was entirely appropriate to enforce the wearing of helmets to limit the safety risks. But it would be inappropriate to limit the race to only straight, wide roads, or to remove downhill racing or to take any number of other measures that would increase safety but ruin the sport as a spectacle and as a cultural practice. It would be a waste of time to take other measures, such as limiting the amount of time or the speed that riders can train at, even on the grounds of safety. It could not be enforced.

Enforceability requires a reasonable limits.“