The appeals tribunal rewrote the law by restricting the rebuttal of work-related presumption: court
The Ontario Superior Court of Justice has quashed a Workplace Safety and Insurance Appeals Tribunal (WSIAT) decision that awarded workers' compensation benefits to three Toronto Fire Department dispatchers diagnosed with breast cancer.
The court ruled that the tribunal unreasonably excluded workplace exposure evidence from the rebuttal analysis, contradicting the statutory language and Workplace Safety and Insurance Board (WSIB) policy.
The case of Toronto (City) v. WSIAT, 2025 ONSC 511 involved three communication dispatchers working for the Toronto Fire Department. Each developed breast cancer and sought compensation under the Workplace Safety and Insurance Act (WSIA). Under Ontario's regulations, breast cancer is an occupational disease for firefighters, and fire dispatchers fall within the statutory definition of "firefighter."
The WSIA establishes a presumption that listed occupational diseases are work-related unless proven otherwise. The City of Toronto, the employer, argued that dispatchers do not face the same exposure risks as frontline firefighters and that this distinction was relevant in rebutting the presumption. The Workplace Safety and Insurance Board (WSIB) initially denied their claims, reasoning that the dispatchers' lack of exposure to hazardous firefighting conditions rebutted the presumption of work-related causation.
The tribunal ruled that parties could rebut the statutory presumption only by proving an external cause, such as genetics or lifestyle factors. It explicitly excluded workplace exposure from the rebuttal analysis, concluding that considering work conditions would undermine the presumption's purpose of simplifying occupational disease claims.
Following WSIB's direction reaffirming that its "Cancers in Firefighters" policy allowed consideration of workplace conditions in the rebuttal process, the tribunal upheld its original decision and denied the employer's request for reconsideration.
The Ontario Superior Court found that the tribunal's interpretation of the rebuttable presumption was unreasonable and inconsistent with the WSIA and WSIB policy. The court ruled that parties could rebut the presumption by proving that employment did not significantly contribute to the cancer diagnosis.
The court emphasized that the tribunal rewrote the law by restricting how parties could rebut the presumption. It ruled that the tribunal had ignored binding WSIB policy, which explicitly permits workplace exposure evidence in the rebuttal process. The tribunal's reasoning lacked a logical foundation, and its approach conflicted with the statutory requirement that the presumption applies "unless the contrary is shown."
The court quashed the tribunal's decision. Rather than sending the case back for reconsideration, the court upheld the WSIB's original determination, which denied compensation based on the dispatchers' lack of exposure to hazardous conditions typically associated with frontline firefighting.
