WSIB Limits on Mental Stress Claims found Unconstitutional

October 27, 2014 | Evan Campbell

In a decision released April 29, 2014, the Workplace Safety and Insurance Appeals Tribunal (“WSIAT”) declared certain provisions of the Ontario Workplace Safety and Insurance Act (“WSIA”) unconstitutional.

The decision (indexed as December No. 2157/09) involved a nurse who was diagnosed with a psychological adjustment disorder which was attributed to workplace stressors. The claimant experienced ongoing harassment from a doctor over a 12 year period. The harassment included yelling and demeaning her in front of colleagues. The worker was effectively demoted when her workplace responsibilities were reduced after she raised her concern regarding the mistreatment with her team leader. The nurse was unable to continue working.

The workers’ claim was denied by the Ontario Workplace Safety and Insurance Board (“WSIB”) and the WSIB Appeals Branch as section 13 (4) and (5) of the WSIA and the WSIB’s traumatic mental stress policy limits claims for mental stress to those who have experienced “an acute reaction to a sudden and unsuspected traumatic event”. Subsections 13(4) and (5) of the WSIA provide as follows:

13(4) Except as providing in subsection (5), a worker is not entitled to benefits under the insurance plan or mental stress.

(5) A worker is entitled to benefits for mental stress that is an acute reaction to a sudden and unexpected traumatic event arising out of and in the course of his or her employment. However, the worker is not entitled to benefits for mental stress caused by his or her employer’s decisions or actions relating to the worker’s employment, including a decision to change the work to be performed or the working conditions, to discipline the worker or to terminate the employment.

The worker appealed the decision to the WSIAT on the basis that the applicable provisions of the WSIA violated her rights to equality as guaranteed by the Charter of Rights and Freedoms. After hearing conflicting medical evidence, the WSIAT concluded that there was a moderate causal connection between job strain and mental disorders. The WSIAT held that the relevant provisions of WSIA create a distinction based on mental disability as they prevent workers with mental illness from establishing a claim based on restrictions that are not imposed on workers with physical injuries. Specifically, a worker with a physical injury is not required to establish that the injury was caused by a sudden and unexpected event. The WSIAT also found that provisions were discriminatory as they perpetuated the historical disadvantage of those with mental illness. As such, the impugned provisions were found to violate section 15(1) of the Charter of Rights and Freedoms.

It remains to be seen how this decision will affect future claims as a decision of the WSIAT tribunal is only binding on the parties to the appeal. Of note, WSIAT found that the portion of section 13 (5) which excludes entitlement for mental stress caused by the employer’s decisions or actions was not before them in the appeal. This restriction may also be challenged in future claims. The Ontario Occupational Health and Safety Act requires that employers protect workers from workplace violence and harassment. Employers need to ensure that they sufficient workplace policies in place and provide adequate training to prevent workplace violence and harassment and limit stress-related lost time claims.


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