The Mitigation Myth Is Dead

Why It Matters

The ruling restores the correct mitigation rule, enabling employers to more effectively reduce damages while forcing employees to meet a higher evidentiary standard when contesting mitigation defenses, reshaping Ontario wrongful‑dismissal litigation.

Key Takeaways

• Ontario Court of Appeal rejects “inferior job” mitigation exemption.
• All earnings during notice period now deductible, regardless of pay level.
• Employers must prove comparable work was actually available to claim mitigation failure.
• Williamson will be cited in future Ontario wrongful‑dismissal cases.

Pulse Analysis

The myth that a dismissed worker could keep all damages despite taking a lower‑paying job originated from a 2017 concurring opinion, not a binding majority ruling. Over nearly a decade, courts and counsel treated the view as settled law, leading to inconsistent damage awards and strategic litigation tactics. By revisiting the original jurisprudence, the Ontario Court of Appeal clarified that mitigation income is mitigation income, regardless of the new role’s status or compensation, restoring the doctrinal foundation that has governed Canadian employment law for decades.

In *Williamson v. Brandt Tractor Inc.*, the appellate panel emphasized two pivotal points. First, any salary earned during the statutory notice window must offset the employer’s liability, eliminating the “inferior‑job” loophole that previously allowed plaintiffs to retain full awards. Second, the burden on employers to prove a failure to mitigate is now two‑fold: they must demonstrate not only that the employee’s job‑search efforts were insufficient, but also that a comparable position was realistically available in the relevant market. This heightened evidentiary requirement protects employees from speculative claims while giving employers a clearer roadmap for defending wrongful‑dismissal actions.

Practically, the decision will reverberate through Ontario’s employment law landscape. Law firms will need to adjust pleading standards, ensuring that mitigation calculations include all earned income and that any failure‑to‑mitigate arguments are backed by concrete market data. Employers should proactively document comparable job openings and maintain detailed recruitment logs to meet the new proof threshold. For employees, the ruling underscores the importance of documenting the quality of alternative offers and the feasibility of securing comparable work. Overall, *Williamson* reestablishes predictability in damages assessments and signals a more rigorous, evidence‑driven approach to mitigation disputes across Canada.