Estey, writing for the court, discusses that in order for volenti non fit injuria to apply as a defence the defendant must prove that the plaintiff, expressly or through implication, agreed to exempt the defendant from liability for any damage suffered by the plaintiff. It will only apply in cases where it can be said that there was an understanding on the part of both parties that the liability had been waived. Obviously, this does not occur very frequently in car accident cases, and even more infrequently in cases involving intoxication, as you must be in the right state of mind to properly agree to waive the other party’s liability.
In applying this to the case at bar Estey decides that it is clear that Dube voluntarily assumed the risk when he took the wheel and that while there had been some confusion with expressing the question of volenti non fit injuria and contributory negligence to the jury at trial, their answers indicated that they had not been confused.