In British Columbia (Workers’ Compensation Appeal Tribunal) v. Fraser Health Authority, 2016 SCC 25, the Supreme Court of Canada affirmed that breast cancers experienced by a group of hospital lab workers were occupational diseases. Overturning the decisions of the B.C. courts, the Supreme Court of Canada restored the Tribunal’s decision on causation. The Court held that the Tribunal was entitled to consider and draw inferences from all of the evidence it found relevant to the issue of causation, including circumstantial evidence. The expert opinion before the Tribunal was not dispositive on the question of causation. The Supreme Court also held that a court on judicial review may not override the Tribunal’s assessment of the evidence on the grounds of insufficiency; if there is some evidence to support the Tribunal’s factual findings, then the Tribunal’s decision is not patently unreasonable.
Fraser Health Authority additionally upheld the B.C. Court of Appeal’s 2014 order that the Tribunal’s decision on an application to reconsider its decision in the case was a nullity. The effect of this ruling is to confirm that the Tribunal cannot reconsider its own decisions for patently unreasonable errors.