Duty To Mitigate

Mitigation is a common law doctrine based on fairness and common sense. As a general rule, a plaintiff will not be able to recover losses that could have been reasonably avoided.1

While a plaintiff bears the burden of proving the fact that he has suffered a loss and the quantum of that damage, the defendant bears the onus of proving, on a balance of probabilities, that:

the plaintiff has failed to make reasonable efforts to mitigate and; that mitigation was possible.2 That doctrine of mitigation has been clearly stated in Red Deer College v. Michaels, [1976] 2 S.C.R. 324, where Laskin C.J. said, at p. 331:

If it is the defendant's position that the plaintiff could reasonably have avoided some part of the loss claimed, it is for the defendant to carry the burden of that issue, subject to the defendant being content to allow the matter to be disposed of on the trial judge's assessment of the plaintiff's evidence on avoidable consequences.3

Requirements to Mitigate

The general rule is that a plaintiff bears no obligation to mitigate, however, damages can be reduced if the plaintiff failed to take reasonable steps to mitigate his losses.4 For instance, the duty for mitigation may not apply when the injured party does not have the financial resources to reduce the damages.

A party that unreasonably fails to mitigate their losses reduces the quantum of damages to the extent that mitigation would have avoided the loss.5 For instance, if the plaintiff's actions partially avoided the loss, then a partial reduction of the damages is justifiable. If the plaintiff takes reasonable steps to mitigate his losses, he may recover the costs and expenses incurred in mitigation of damages.

The valuation of damages is, therefore, a “balancing process” as the Federal Court of Appeal stated in Redpath Industries Ltd. v. Cisco (The): “The Court must make sure that the victim is compensated for his loss, but it must at the same time make sure that the wrongdoer is not abused.”6

The requirement to take steps to mitigate losses is one such responsibility and it is argued by a party seeking justice in the particular circumstances of the case.

Mitigation in Property Damage Claims

The plaintiff's duty to mitigate can apply to events leading up to the loss and post-loss depending on the circumstances of each case. In any event, the general principle is that the duty to mitigate applies to claims for breach of contract and tort.

A plaintiff's duty to mitigate damages in...