TORONTO — A garage owner will get a chance to argue before the Supreme Court of Canada that he should not be held responsible for the terrible injuries a teen suffered when he and a friend stole a car from the lot and crashed it.

Canada’s top court agreed last week to hear the highly unusual case in which the injured teen successfully sued the garage for leaving the car unlocked and its keys in the ashtray.

Court records show the teens had been drinking and smoking marijuana when they trespassed on Chad Rankin’s property in Paisley, Ont., late on an evening in July 2006. One of the teens, then 16, decided to steal a Toyota Camry even though he had never driven before.

The duo headed to Walkerton but never made it. The passenger, who can only be identified as J.J., was left with catastrophic brain injuries in the ensuing crash. J.J., then 15, sued his friend and his friend’s mother as well as Rankin for negligence.

Superior Court Justice Johanne Morissette determined Rankin owed J.J. a duty of care because, among other things, people entrusted with motor vehicles “must assure themselves that the youth in their community are not able to take possession of such dangerous objects.”

The jury then found the injured teen and the defendants negligent, but laid the bulk of the blame — 37 per cent — on the garage owner. In doing so, jurors cited the fact that the car was unlocked, the key was in the vehicle, and that Rankin should have known there was a risk of theft. They also faulted him for the overall lack of security.

Last October, Ontario’s Court of Appeal refused to overturn the trial verdict, saying that Rankin did indeed owe J.J. a duty of care — although not for the reasons Morissette had stated. It also found the jury’s findings reasonable.

“On the face of things, the notion that an innocent party could owe a duty of care to someone who steals from him seems extravagant, but matters are not so simple,” Appeal Court Justice Grant Huscroft wrote for the panel. “It is well established that the duty of care operates independently of the illegal or immoral conduct of an injured party.”

In this novel case, the Appeal Court found ample evidence supported the conclusion of “foreseeability” that a car might be stolen.

Trial witnesses, the court noted, testified that Rankin’s Garage routinely left cars unlocked with the keys inside, while other garages used lock-boxes or took other measures to secure the keys. Rankin himself testified that the witnesses had lied, saying he kept keys in a safe, and checked every night that vehicles were locked.

In addition, evidence was that the garage took no measures to keep people off the property when it was closed, there had been a previous auto theft from the lot, and joyriding in the area was common.

“The risk of theft was clear,” Huscroft wrote. “It was foreseeable that minors might take a car from Rankin’s Garage that was made easily available to them.”

Rankin, Huscroft found, had abrogated his responsibility for securing the cars against theft by minors like J.J. and while a different jury might have parcelled out the blame differently, its conclusions were not unreasonable. The court also ordered Rankin to pay J.J. $30,000 in legal costs.

It’s not clear when the Supreme Court will hear the case.