• According to the 3rd edition of Law of Contract by Fridman (p.282), “there have been times when the interpretation given by the courts has been so narrow as to apply to only those persons demonstrating a disability akin to blindness or mental infirmity. At other times the doctrine has been used with a more curative philosophy.” He described the general trend in case law on non est factum as follows: “Subsequent cases have accepted and applied the Saunders and Marvco cases. ... It is a difficult matter to invoke the plea successfully. The onus of proof is heavy upon a party raising the plea. ...Where the plea has been successful, it has been because the party signing the document was ignorant of the English language and did not know what was going on; or was of limited education and reading ability and was mistaken as to what the document was” (pp. 291–292).

Legal requirements for successful plea

• The decision in Voukelatos v. Canada (Minister of National Revenue), [1991] T.C.J. No. 1120 (T.C.C.) suggests that the following questions should be examined when considering a plea of non est factum: “Was such a party an experienced business person? Was it a novel situation? What, if any, representations were made by the other party to the contract, that party’s solicitor, or others? Was the party signing careless as a result of his or her age, literacy, level of education, experience in business? And was such carelessness the appropriate standard of behaviour for a person in such a situation? Was it reasonable for the party to rely upon the other party’s statements or representations, or those of a solicitor, bank manager or similar person? What were the abilities of such a person to understand the nature and effect of what (s)he was signing? Was it reasonable for such a party to sign the document without reading it or asking to have its contents and effect explained?” [emphasis added].