The International Olympic Committee (IOC) is the regulating body of the Olympic Games, and as such, it has the authority to judge athletes in violation of Olympic laws, for which their Olympic medals may be revoked (i.e. rescinded). The guilty athlete must return stripped medals to the IOC. An example of this occurred at the 2008 Beijing Olympics when Chinese judoka Chen Jingxuan was caught using a drug that enhances muscle contraction. Chen was given a one-year suspension by the Chinese Judo Association and had her medals withdrawn. At the IOC's request, China allowed Chen to retain her gold medal after she served her suspension. If an athlete is found to have committed fraud or manipulation of any kind, then they lose all rights to their medals. An example of this would be if an athlete was discovered to have used anabolic steroids or other performance-enhancing drugs (PEDs) during competition; they would be disqualified from all future events controlled by the anti-doping system. Their previous victories would not be vacated however, because doing so could allow someone to compete cleanly with tainted drugs in their system. For most violations, including doping, there are levels of punishment ranging from a warning to disqualification from all future competitions. In general, more serious infractions will receive a harsher penalty. For example, an athlete who fails a drug test may be suspended for several months or permanently banned from competition.