Disappointed beneficiaries are often captivated by the idea of undue influence. But proving undue influence is not a straightforward matter, as we can see in the reasons of Justice J. deP. Wright in Zerbinati v. The Children’s Lawyer et al.
The case is worth a read because, well, it is case law, which we all love to read inside at one’s computer on a sunny Sunday afternoon. But also because the reasons are so evocative; they tell an almost cinematic story of a couple who immigrated to Canada from Italy and, in very humble economic conditions, raised four successful sons, the youngest of whom is preferred by the impugned Will. The other three sons brought an application challenging the Will on various grounds, including undue influence.
There were no suspicious circumstances alleged or proven, so the onus was on the applicants to prove undue influence.
The Court summarized the relevant authorities on this subject in the following succinct passage:
Burden Of Proof
 The burden of proof of undue influence is on the attackers of the will to prove that the mind of the testator was over borne by the influence exerted by another person such that there was no voluntary approval of the contents of the will. Suspicious circumstances may rebut the presumption of testamentary capacity and knowledge and approval of contents, so as to place the onus on those who advance the will, but the burden of proving undue influence or fraud remains on those who allege it. (The leading case is Vout v. Hay, 1995 CanLII 105 (SCC),  2 S.C.R. 876.)
 The burden is the civil burden of the balance of probabilities. (Vout ¶24)
 There is no fiduciary presumption of undue influence in the case of wills.(Stephens v. Austin,  B.C.J. No. 470, 50 E.T.R. (2d) 255)
Definition of Undue Influence
 To amount to sufficient undue influence to upset a will the influence exerted on the testator must usually have amounted to coercion, i.e. The testator must have been put in such a condition of mind that if he or she could speak his or her wishes to the last he or she would say, “this is not my wish but I must do it.” (Feeney’s Canadian Law Of Wills ¶3.10)
 Cullity J., in Scott v. Cousins,  OJ No.19 ¶ 113 quotes Williams and Mortimer, Executors, Administrators and Probate (17th ed., 1993) pg. 184:
Thus undue influence is not bad influence but coercion. Persuasion and advice do not amount to undue influence so long as the free volition of the testator to accept or reject them is not invaded. Appeals to the affections or ties of kindred, to the sentiment of gratitude for past services, or pity for future destitution or the like may fairly be pressed on the testator. The testator may be led but not driven and his will must be the offspring of his own volition, not the record of someone else’s. There is no undue influence unless the testator if he could speak his wishes would say “this is not my wish but I must do it”.
“The testatrix does not have to be threatened or terrorized; effective domination of her will by that of another is sufficient” Crompton v. Williams 1938 CanLII 66 (ON SC),  O.R. 543 p. 583.
 But undue influence is also linked with fraud. In my opinion, if the testator would have said “he deliberately led me to believe. . . That was wrong. If I had known the truth I would never have signed that” then the will may be impeached.
 Circumstantial Evidence:
“Undue influence is a subtle thing, almost always exercised in secret, and usually provable only by circumstantial evidence” Cullity J. in Scott v. Cousins,  OJ No.19 ¶ 48 citing Atkinson on Wills (2nd edition, 1953) pg. 638
 Variation From Previous Wills
“The fact that the will departs radically from the dispositive pattern of previous wills has also been regarded as having some probative force.” Cullity J. in Scott v. Cousins,  OJ No.19 ¶ 114
Several witnesses described alleged attempts on the part of the favoured son to estrange the applicants from the Testator. However, there was also evidence that the estrangement of the applicants arose from their own complicated relationship with their parents. As Justice Wright observed: “One by one, as each of the three eldest boys matured the unstoppable force of the father met with the immovable object of the son and the son launched out to make his own way in life.”1
Despite finding that the favoured son was “intense”, “self-centred” and manipulative, the Court held that the Will was not the product of undue influence. The strong-willed nature of the Testator and the lack of any issues concerning capacity were also factors that supported the validity of the Will.
Incredibly, the trial of the issue of undue influence took place over fifteen days (!), which raises questions about the costs of these proceedings. Alleging, but failing to prove, undue influence can sometimes result in costs payable by the applicant. A fifteen-day trial is no doubt costly. At the time of writing, the costs decision has not been reported.
And I know, dear reader, that you want me to tell you the size of the estate, because you are no doubt wondering how much money is at stake in a 15-day trial. And I also know that if I told you that information was never put to the Court, you would not believe me, so I will leave you with the words of Justice Wright:
If I were to be asked how much money is at stake in this dispute I would be unable to answer. Over approximately 5 weeks of hearing the size of the estate was never mentioned. Like so many family actions what seems to be important are relationships and feelings.2
 Zerbinati v. The Children’s Lawyer et al, 2014 ONSC 4565 (CanLII), at para 21.
 Zerbinati v. The Children’s Lawyer et al, 2014 ONSC 4565 (CanLII), at para 4.