Behind every doping scandal in sport lurks the World Anti-Doping Code, the International Olympic Committee's rulebook on combating drug taking. Before today, the Code had to be followed by every Olympic sport without exception. The IOC had such clout that this year FIFA had to change their doping code after the Court of Arbitration in Sport ruled that it was different from the Code. However, the decision of the European Court of Justice in the case of two banned swimmers, Meca-Medina and Majcen, may have changed all that.

The pair had been complaining about the International Olympic Committee (IOC) to European institutions since 2002. They complained first of all to the European Commission, then to the European Court of First Instance (CFI) and finally to the European Court of Justice (ECJ). On 23 March 2006, the Advocate General gave his opinion on the matter and the final ruling of the ECJ was published on 18 July 2006.

In essence, the two swimmers argued that the IOC along with its 27 accredited laboratories were carrying on a concerted practise which was a barrier to the swimmers' ability to fairly compete within their market. The core of this practise was the IOC's own anti-doping code, the forerunner to the World Anti-Doping Code currently in force.

The ECJ ruled that the application of an anti-doping code had to be strictly proportionate to the circumstances of each case (e.g. as to the dividing line between the legitimate and illegitimate presence of banned substances and the severity of sanctions imposed). Every sport is different, and the punishment given to sportspeople in certain sports may be too rigid or severe to be proportionate under European competition law.

This judgment could have wide-ranging effects for the World Anti-Doping Code. Sportspeople will now be free to challenge any punishment given under the Code by arguing it is disproportionate. It means that bans such as Linford Christie's five-year ban after being found guilty of doping on a technicality, could be a thing of the past.

But deeper than that, this opens up the IOC's anti-doping fight to legal challenge. For the first time, anti-doping rules in sport are subject to European competition law. The IOC might now have the European Courts looking very closely at their Code. The one-size fits all approach may no longer work. Some sporting bodies could argue that they know better than the IOC what punishments should be given to their members.

Governing bodies such as FIFA may now be able to have an anti-doping code that is different from the IOC's Code. Different sports could have different maximum levels of drugs allowed in the system, arguing that anything higher/lower would mean athletes were being excluded unfairly. The World Anti-Doping Code could be blown apart, with the IOC losing control over doping in sport.