In a case that will affect workers’ compensation boards across the country, the Supreme Court of Canada has announced a landmark decision. It ruled in favour of three women who were lab workers at the Mission Memorial Hospital.
All three developed breast cancer on the job, and were denied compensation by WorkSafe B.C. — the provincial workers’ compensation board.
An investigation showed that between 1970 and 2004, seven women at the lab had fallen ill with the disease. All survived.
However, medical experts testified they could find nothing that would link the work environment with breast cancer. Specifically, they examined the chemicals and equipment used in the lab, and reported: “We did not find any scientific evidence for the plausibility of a laboratory work-related [cause] regarding breast cancer.”
On that basis, the request for compensation was denied. The three employees then went to court.
In deciding the matter, the court had two questions to resolve. First, could a cancer cluster that size have occurred purely by chance? The statistical evidence indicated this would be unlikely.
Among the lab’s female workforce of 57, one case of breast cancer might have been expected during the period in question, that being the incidence of the disease in the broader population. However, seven cases go well beyond normal.
Of course, mathematically improbable events occur all the time. The chances of red coming up 10 times in a row at roulette are fewer than one in 1,000. And yet it happens, as any casino addict knows.
Nevertheless, the justices accepted that chance alone could not have explained what occurred. This was the court’s only realistic option, given the statistical evidence available at the time. (Notably, the lab has experienced no more cancer clusters in the intervening years, despite retaining the same safety protocols).
The second issue to be resolved was more difficult — and far more consequential. Accepting that seven breast cancers were likely not due to chance, what other explanations were there?
And here the court adopted a line of reasoning that appears to alter worksite law. The judges had medical testimony that made it highly improbable that workplace hazards were to blame for this form of cancer.
The judges acknowledged that finding, but then set it aside: “Causation can be inferred — even in the face of inconclusive or contrary expert evidence — from other evidence, including merely circumstantial evidence.”
Part of the court’s reasoning is understandable. Worksite law requires that where a case is evenly balanced, the issue must be resolved in the workers’ favour.
Yet part of it is also confusing. What counts as “circumstantial evidence”?
The court appeared to be saying that since the employees worked in a lab, and labs have hazardous materials, that is sufficient to settle the matter.
But while this might sound like a common-sense principle, how does it work in practice?
Mission is downwind from 91Ô´´â€™s industrial heartland. Could that be to blame? With no science to guide us, how do we proceed?
This judgment broadens significantly the principle that employees get the benefit of the doubt. And presumably it applies to any workplace injury. That would seem to open the door to many more claims for compensation.
Of course, if employees are harmed on the job, they have every right to redress, although companies also have something at stake here.
Workers’ compensation claims are paid for by employers. If monetary awards rise, so does the cost of doing business.
We don’t yet know if this decision can be absorbed within the finances of WorkSafe B.C. and its counterparts across the country.
We also don’t know if laboratories really do pose a risk for breast cancer. Let’s hope they do not.
