Expert Testimony In Environmental Claims: Participant Vs Litigation Experts

The Ontario Court of Appeal has recently discussed the drafting of expert reports and the nature of expert testimony (respectively in Moore v Getahun, 2015 ONCA 55 (CanLII) and Westerhof v Gee, 2015 ONCA 206 (CanLII)). Neither of these cases related to environmental claims, but both have implications relating to the rules under which experts might testify in environmental cases. This article will discuss the Westerhof case in that vein. The question at issue addressed the very core of what constitutes an "expert" witness: to whom do the expert witness provisions in the Ontario Rules of Civil Procedure apply? Do they apply to anyone offering an expert opinion?

Often in environmental claims more than one expert will testify at trial. For example, in a contaminated land case, the expert who carried out the remediation might testify, while an opposing expert might be called to give an opinion as to whether that remediation was carried out appropriately. Both involve