TORONTO -- A teenage student would not have drowned during a school canoeing and camping trip to Algonquin Provincial Park had he been wearing a life jacket to swim, the teacher who led the multi-day excursion acknowledged during trial Wednesday.

Prosecutors pressed Nicholas Mills, a teacher at Toronto's C.W. Jefferys Collegiate Institute, on his reasoning for allowing 15-year-old Jeremiah Perry to be in the water without a life jacket, given that the teen had failed a mandatory swimming test prior to the trip.

Crown attorney Anna Stanford suggested Perry would still be alive had Mills enforced a rule -- set by the Ontario Physical and Health Education Association, and imposed by the school board -- that requires poor swimmers to wear life jackets at all times while in the water, not just while canoeing.

Mills agreed Perry would not have drowned, but maintained he believed the student was able to swim, and suggested the rule would thus not have applied to him.

"If he was wearing a life jacket, that wouldn't have happened, you're right," Mills said under cross-examination Wednesday.

But Perry was "a swimmer" and had been tested, he said. "My impression is that Jeremiah would not have been in a life jacket" under those criteria, he said.

Perry was swimming with his canoe group when he vanished in the waters of Trout Lake on July 4, 2017. His body was found by police divers the next day.

Mills, his partner and a lifeguard were supervising at the time of Perry's disappearance, as was another student who had lifeguard training, court has heard.

The judge-alone trial has heard Perry failed a mandatory swim test held at Sparrow Lake ahead of the trip. In total, nearly half the students taking part in the canoe excursion -- 15 out of 33 -- had failed the test, court has heard.

Perry and several others also wore life jackets during the assessment, which was against the OPHEA rules for overnight canoe trips, court has heard.

Students who failed the test were supposed to be offered swimming lessons and a second assessment, and provided with an alternate outing if they failed that, court has heard.

But Mills said earlier this week there was no plan to provide those supports since it was "highly unlikely" anyone would be barred from the outing over the results of the initial test.

The teacher has repeatedly said he believed at the time that Perry had passed the test, and recalled seeing what he thought was a "P" for "pass" next to the boy's name when he "scanned" the test results.

The teacher also said he assessed Perry's swimming abilities again on July 2, and the teen passed.

The Crown alleges the teacher made up both those things after Perry's death so he could claim to have "personal knowledge" of the teen's swimming abilities and justify letting him participate in the outing and swim without a life jacket.

Mills knew he would be blamed for the incident and was worried about the fallout, since he had knowingly breached several rules and lied about it to school board officials, the Crown suggested.

"I'm not suggesting that you were not devastated by this.... but when Jeremiah drowned you also realized you were in a great deal of trouble," Stanford said.

"I knew there would be, certainly, investigations. I knew that I had breached OPHEA and there would be some consequences from that, for sure," the teacher said.

He rejected the Crown's suggestion that he feared losing his job, saying he expected the school's principal and vice-principal would come forward to say they had approved the changes and that the trip was safe.

The teacher said he believed he would face an internal investigation and likely one by the the provincial regulator, the Ontario College of Teachers.

"I didn't imagine this, that's for sure," he said.

This report by The Canadian Press was first published June 30, 2021.