VANCOUVER -- As a high school student living on B.C.'s Salt Spring Island, Calder McCormick had a dream of becoming a carpenter after graduation.

But in the early morning hours of Sept. 16, 2012, everything changed.

The night before, 17-year-old McCormick attended a house party and ended up leaving in a vehicle driven by another teenage party-goer. The car ended up going off the road, killing the driver, 18-year-old Ryan Plambeck, and leaving McCormick with a life-altering injury.

Now 24, McCormick is suing the people he says hosted the party at their place. The potentially precedent-setting case, which will examine the question of social host liability when teens are drinking at someone’s home, is now being heard in court in Vancouver.

The notice of civil claim alleges underage teens were drinking at the property of Stephen and Lidia Pearson on Sept. 15, 2012.

In court documents, McCormick is alleging the couple “...allowed access to...or facilitated the consumption of alcohol or other substances to excess by their minor-aged guests” and “...failed to take any or any adequate steps to ensure their minor-aged guests, including the Plaintiff, were reasonably safe when they departed the Party.”

McCormick’s lawyer Michael Wilhelmson told the court in his opening statement toxicology evidence relating to Plambeck will show alcohol impairment was likely a contributing factor in the crash. McCormick testified he was also drinking that night.

The Pearsons deny all of the allegations, saying in their filed response to the claim McCormick made a voluntary decision to drink: “His age and experience was such to leave him accountable and responsible for his choices notwithstanding his legal status as a minor.”

None of the claims has been proven in court.

Wilhelmson said his client suffered a traumatic brain injury and currently resides in an assisted living facility.

“These types of injuries, they affect their memory, they affect their mental processing, and from what all our experts are saying, he’s effectively competitively unemployable,” Wilhelmson told CTV News Vancouver. “He will never have the life he had before, it’s over.”

Wilhelmson said McCormick is seeking a finding from the court that a duty of care is owed by the adults and the standard of care was breached.

"What happens when you have these parties with minors over? And are there special positive duties to act to protect them?” Wilhelmson said. “Once that kid is in your space, on your property, you're allowing them to drink alcohol, you're facilitating a risk. Can you just wash your hands of the matter? I’m talking generally. Or must you take certain steps to identify the risks and take steps to prevent those risks from manifesting in a whole number of different ways?”

McCormick testified he wasn’t planning on going to the party initially, but friends convinced him to go.

A lawyer for the defendants said they would not be commenting publicly at this point.