It is unclear what could be meant by “demolishing” a CRA assumption of FMV, which is a matter of opinion

Preston stated: “A statement that an identified property has a particular fair market value at a particular point in time is an assumption (or finding) of fact, notwithstanding that fair market value has a legal definition. Fair market value is predominantly factual … .”

It is suggested that fair market value (FMV) is not a “fact” in the sense provided by Phipson on Evidence, namely, “a statement that can be verified”, i.e., “can be proven to be true or false through objective evidence”, whereas evidence as to FMV is essentially opinion evidence. In other words, “fair market value is not a fact that can be rebutted by proving it to be false.”

This last proposition generates difficulties in applying the dictum of L’Heureux-Dubé J in Hickman Motors that if the taxpayer meets its initial onus of “demolishing” the Minister’s assumptions through making out a prima facie case, the onus shifts to the Minister. Thus:

If a fair value is neither true nor false, nor more likely than not to be true or false, it cannot be proven. The initial onus on the taxpayer to “demolish” the Minister’s assumption by presenting enough evidence to create a rebuttable presumption that the matter assumed is false cannot be met, nor can the subsequent onus on the Minister “to prove” that the assumption is true.

(Note that although this shifting-onus doctrine is well entrenched in the Quebec Court of Appeal, it was suggested to be incorrect by Webb JA in Sarmadi and Eisbrenner, whose comments were endorsed by Monaghan JA in Kufsky.)

Neal Armstrong. Summary of David H. Sohmer, “Is Fair Market Value a Fact?,” Tax Topics (Wolters Kluwer), 10 October 2023, No. 2689, p.1 under General Concepts - Onus.