Maria Sharapova was banned for taking medication which was allowed at the time, just because traces of it were found later on. Her "didn't know" was not enough. Simona Halep also didn't get much consideration. However Jannik's "didn't know" worked quite well. Serena even didn't let WADA officials in to take the probe and got away with it. So it's not really important if you're"dirty" or "clean", what is imore important which country you are from...