1. Under a well established CAS jurisprudence, in order to determine whether an act constitutes an anti-doping rule infringement, the Panel applies the law in force at the time the act was committed. In other words, new regulations do not apply retroactively to facts that occurred prior to their entry into force, but only for the future. The principle of non-retroactivity is however mitigated by the application of the “lex mitior” principle.