The case involves a Spanish gymnast, D., who appealed to the Court of Arbitration for Sport (CAS) against sanctions imposed by the International Gymnastics Federation (FIG) following multiple positive doping tests for cannabis (THC). The CAS had full authority to review the case under Article 57 of the Code of Sports Arbitration, allowing it to re-examine all factual and legal arguments and render a final decision, thereby correcting any procedural flaws from prior instances. D. tested positive for THC in three competitions: the Spanish Championships (October 2002), the Paris World Cup (October 2002), and the World Championships in Debrecen (November 2002). The Spanish Federation (RFEG) suspended him nationally for three months, while the FIG imposed a separate three-month international suspension, disqualification from events, and forfeiture of prizes. D. and the RFEG appealed, arguing procedural violations, double jeopardy (non bis in idem), and the retroactive application of the World Anti-Doping Agency’s (WADA) code, which no longer classified cannabis as a doping substance. They claimed the FIG’s sanctions were unjust given prior lenient precedents and that the delayed proceedings caused undue harm. The FIG countered that the CAS’s comprehensive review power nullified procedural defects, that the national and international sanctions addressed distinct matters (thus avoiding double jeopardy), and that applying WADA’s code retroactively would create unfair treatment among athletes. The FIG also asserted D.’s repeated cannabis use, supported by expert testimony, justified the sanctions. The CAS ultimately upheld the FIG’s sanctions, dismissing the appeal on all grounds, including the inapplicability of the lex mitior principle (favoring milder penalties under new laws) due to the WADA code’s non-retroactivity. The decision reinforced the FIG’s authority to impose independent sanctions for doping violations and clarified the limits of procedural challenges in arbitration. The case highlights the complexities of anti-doping regulations and the importance of timely and transparent disciplinary processes in sports, ensuring compliance with legal standards and procedural fairness. The ruling underscored the seriousness of repeated doping violations and the need for consistent enforcement of anti-doping regulations, ultimately dismissing D.'s appeal and affirming the sanctions as lawful and proportionate.