James Armstrong, a wheelchair curler and former dentist, appealed a doping violation decision by the World Curling Federation (WCF) after testing positive for Tamoxifen, a prohibited substance, during an out-of-competition test in December 2011. Armstrong argued the substance entered his system unintentionally, as he had stored his late wife’s Tamoxifen medication alongside his own in a shared container, leading to accidental ingestion. The WCF Panel reviewed his case, considering his medical history and clean doping record, but concluded his storage method lacked the "utmost caution" required, imposing an 18-month suspension. Armstrong appealed to the Court of Arbitration for Sport (CAS), seeking a reduction or overturn of the sanction, citing disproportionate punishment and procedural errors. The CAS upheld the WCF’s finding of negligence but ruled the 18-month suspension was "evidently and grossly disproportionate," reducing it to six months. The CAS emphasized that while Armstrong’s actions demonstrated negligence, his circumstances—including emotional stress following his wife’s death and the unintentional nature of the ingestion—warranted leniency. The panel distinguished his case from others involving dietary supplements, where athletes knowingly took risks, and noted the absence of intent to enhance performance. The CAS also criticized the WCF Panel for incorrectly applying legal standards, such as assessing fault under Article 10.5.2 instead of Article 10.4, which focuses on the level of fault. The final decision highlighted the importance of context in evaluating negligence and proportionality in anti-doping cases, setting the suspension period from March 6 to September 5, 2012. The ruling underscored the need for athletes to exercise extreme care with medications while ensuring sanctions align with the degree of fault and specific circumstances.