The night began with a pillowcase being thrown over the student's head and ended with him on the floor of his dorm room, covered in vomit and unable to communicate.

In between, the first-year McGill University student, along with other rookies on the varsity basketball team, had a 40-ounce bottle of malt liquor duct-taped to his hands, with orders to finish it in 20 minutes.

He was also made to drink vodka and other alcohol while teammates held back his head, and then forced to strip down to his underwear to play sex-themed games with rookie members of the women's team.

Those are among the alleged details of a hazing in September 2015 revealed in a letter by the student shared with CBC News.

"Perhaps it would have been easier for me to just keep quiet," wrote the student, who asked not to be identified.

"I'm not out to destroy anyone or get revenge against McGill or anyone at McGill, but I'm worried that something tragic is going to happen and I don't want that on my conscience."

​Ollivier Dyens, McGill's deputy provost, confirmed to CBC News that the university is aware of the hazing party.

He said McGill's administration learned about the incident soon after it happened, but at first decided not to investigate after speaking with the student's mother.

"She specifically asked us at that point not to talk to anyone. So we could not inquire at that point," he told CBC Radio's Daybreak.

"When somebody asks you not to investigate to protect a student's well-being, this has to be taken into consideration. Because the whole point is, how do we help the player move forward?"

"Really, our first objective was the student's well-being. The second objective was to make sure these things never happen again."

School abandons zero-tolerance policy

The booze-filled night points to the Montreal university's struggle to crack down on hazing, more than a decade after another high-profile incident.

In 2005, D'Arcy McKeown, an 18-year-old rookie football player, was sexually assaulted with a broomstick by an upperclassman as teammates cheered him on.

The case made headlines across the country and, following an investigation, the university introduced a zero-tolerance policy toward hazing and scrapped the football season.

The McGill Martlets, shown here celebrating after winning the Canadian University basketball gold medal match 66-55 over Laval Rouge et Or on Sunday, are on probation for the team's participation in hazing in 2015. (Chad Hipolito/Canadian Press)

In the latest incident, Dyens said an investigation was eventually conducted, and both the men's and women's basketball teams were sanctioned.

The men's team was put on probation for this year and next year, while the women's team, which just won the national championship, was put on probation for this year.

Dyens wouldn't elaborate on the terms of the probation. McGill's report into the incident has not been made public.

The incident has prompted McGill to reconsider its approach.

"Being more harsh is not always the solution," Dyens said.

"We tell the players, 'Don't do this, this is serious, there will be measures, don't do it, this is serious.' At one point, what happens outside of this campus, at private parties, there's a limit. There's a limit to what we can do."

Pressured from teammates

In his letter, the student says he and another player had been sick not long before the hazing and tried to get out of participating in the ritual, but a "veteran player advised that it had been happening for five years and no rookie had ever refused to attend this party, and that if we didn't attend, it was going to be a long year for both of us."

He was taken to an apartment with the pillowcase over his head, he said, where players and alumni at the hazing event were instructed not to take pictures and to put away their phones.

During the round of drinking games, he said, he witnessed another intoxicated rookie "fall face first onto the floor without making any attempt to break his own fall."

"I heard his head crack on the ground, and he appeared unconscious with white foamy liquid coming out of his mouth," he wrote. As for his own state, he said he eventually managed to stumble home without his shoes.

"A friend came to my dorm room and found me, the floor and my bed covered in vomit, unable to properly communicate."

McGill not doing enough, mom says

Sheilagh D'Arcy McGee, the mother of D'Arcy McKeown, the student assaulted in 2005, said the university clearly isn't doing enough to prevent hazing rituals.

She said the school should have ordered an investigation as soon as it was informed of the hazing party.

Her son left McGill after being assaulted as part of the football team's rookie initiation. He later attended the University of Toronto, where he played football.

"It robbed my son of his dreams and promise of playing football and attending McGill, and it's pretty much the same thing in 2015 with this basketball player," D'Arcy McGee said.

Dyens said McGill has repeatedly told university teams to abstain from hazing rituals. At this point, he said, changing the culture may have to come from the players.

"They have to understand that the best way to create team experience and improve team-building is positive reinforcement," he said.