On April 29, 2014, the Workplace Safety and Insurance Act Tribunal (“WSIAT”) issued a decision regarding a worker’s entitlement to benefits for chronic mental stress under the Workplace Safety and Insurance Act (“the Act”). In its decision, the WSIAT determined that the provisions in the Act which limit a worker’s entitlement to coverage to stress that “...arises from an acute reaction to a sudden and unexpected event” violate the equality guarantee in s. 15 of the Charter of Rights and Freedoms. The WSIAT found that the infringement was not “saved” by s. 1 of the Charter, and that consequently, both the legislative provisions and the WSIB policy implementing them were unconstitutional.

The decision arose out of the denial of WSIB benefits to a nurse who claimed that she had been subjected to ill treatment by a colleague for a period of 12 years, resulting in chronic mental illness that prevented her from working. There was no physical assault or threat of violence – the injury was purely mental in nature. Ultimately, the WSIB determined that the worker’s claim did not satisfy the requirement in s. 13 of the Act that a worker will only be entitled to benefits for mental stress where the stress is an “...acute reaction to a sudden and unexpected traumatic event arising out of and in the course of employment.”

In reconsidering the WSIB’s decision, the WSIAT determined that the limitation on a worker’s ability to receive benefits in relation to mental stress was discriminatory, and served only to perpetuate the prejudice and stigmas associated with mental illnesses. The Attorney General of Ontario unsuccessfully argued that the difficulty in demonstrating causation in the  case of mental illnesses constituted a justification for treating them differently than physical disabilities.

Disagreeing with this approach, the WSIAT held that the relevant portions of s. 13 of the Act, as well as the Board’s Traumatic Mental Stress Policy with respect to mental stress, were both unconstitutional, and should not be applied.


The implications for Laurie Johnson’s WSIB claim are clear: she is now more likely to be approved for benefits in relation to the mental illnesses she claims are the result of workplace harassment. If the WSIAT’s position in Decision No. 2157/09 is applied by the WSIB, Ms. Johnson will no longer need to demonstrate that the mental stress she suffers from is the result of an acute reaction to a sudden and unexpected traumatic event. The result is a lower threshold for demonstrating that mental stress falls within the WSIB regime. In sum, this WSIAT decision renders it more likely that her mental illnesses will be covered by WSIB benefits.

It should be noted that, given the involvement of the Attorney General of Ontario, there will likely be a judicial review of Decision No. 2157/09. The implications it has for opening the floodgates to workers’ claims related to everyday stresses that arise in the workplace are significant, and could be presumed to result in substantially higher costs for both the provincial government and employers (in terms of their premiums) alike.