The Crown brought a Mohan application to qualify an expert ergonomist, Steve A. MacDonald, in line of sight, visibility, and human factors, in a case where the defendant was charged under the Occupational Health and Safety Act following a workplace fatality.
The defendant opposed the application.
The court applied the two-stage Mohan/White Burgess test for expert evidence admissibility.
It found the expert's opinion unnecessary as the trier of fact could form conclusions without it, given the direct eyewitness testimony and video evidence.
Furthermore, the court determined that the expert was not properly qualified in the specific narrow area of expertise due to limited prior experience in LOS assessments and reliance on unverified and contradictory factual assumptions.
The court concluded that the risks of admitting the unreliable and unnecessary evidence outweighed its potential benefits, and therefore dismissed the application to qualify the expert witness.