The woman, who spoke at the hearing, had snorted cocaine prior to arriving at the hotel Barber was staying at, and again in the hotel bathroom upon arrival.
Barber was unaware of either deed at the time, stating the woman's behaviour was normal, if a little tipsy (she had offered him a drink of alcohol, which he turned down), and he did not pick up on anything odd or different while kissing her.
After half an hour, the sexual encounter had concluded, with Barber going back to his hotel room and slept.
At the hearing, the Canadian Centre for Ethics in Sports (CCES) argued that the 22-year-old should receive a doping ban of four years because of his violation, although they did not oppose Barber's argument that the most likely source of cocaine found in his system was from kissing the 26-year-old woman.
Barber argued that the most relevant precedent was established in a 2009 Court of Arbitration for Sport (CAS) decision, when CAS considerably reduced tennis player Richard Gasquet's ban for cocaine usage.
In that case, Gasquet argued in similar fashion to Barber, stating that cocaine entered his system after meeting up with and kissing a woman named "Pamela" while on a night out.
The CCES argued against Barber, saying no matter the precedent established in the Gasquet case, Barber didn't demonstrate enough attention to detail for a finding of "no fault or negligence."
Therefore, the central question the arbitrator had to answer was: "Shawnacy Barber's choices and conduct on the night of July 8, 2016 may be viewed as risky, careless and foolish in many different ways. But the issue is, were they risky in the sense of exposing him to the possibility of ingesting a prohibited substance?"
Due to the fact that the 2015 IAAF World Championships winner had asked for a drug-free woman in his advertisement on Craigslist, that he had declined an offer from the woman to drink alcohol, and that the woman said there was no way in which that Barber could have known that she had snorted cocaine, it was deemed that Barber's case was effectively the same as Gasquet's, and struck his period of ineligibility.
His win at the Olympic trials, which doubled as the Canadian Championships, was thrown out, however, while Barber eventually went on to finish the Olympics in a disappointing 10th place.