After considering all circumstances, the CAS confirmed that Stewart “had indisputably committed an anti-doping rule violation under the CAD,” and the 16-month suspension was “a fair and appropriate sanction.”The CAS said that Stewart “did not take any precautions whatsoever” to avoid the anti-doping rule violation. The CAS also said that Stewart’s attitude towards the FIM Anti-Doping Code was “one of reckless disregard.”The Yoshimura Suzuki RM-Z450 pilot Stewart – a two-time 450SX Champion – was screened during the FIM’s random drug test April 12, 2014, at Seattle Supercross. Stewart tested positive for amphetamines from his prescribed Adderall.The FIM said Stewart’s urine sample revealed the presence of a prohibited substance (amphetamine) listed in the category S6. The stimulant was under a.) Non-specified Stimulants and prohibited in competition under the FIM Anti-doping Code (CAD) in force.Though Stewart argued he had received approvals for the use of Adderall, the FIM said at the “moment of the test, Mr Stewart was not in a possession of any Therapeutic Use Exemption (TUE) for that substance.”Due to the suspension, which is pro-rated to April, Stewart was forced to sit out the 2015 AMA Supercross Championship.The suspension will be lifted on August 11, which means Stewart will miss the opening four rounds of 2015 Lucas Oil Pro Motocross.