Undue influence occurs when another person pressures, coerces, manipulates, or controls a testator to such a degree that the resulting will no longer reflects the testator’s own free intentions. It can arise through dependency, intimidation, isolation, or other forms of control, and it often occurs privately rather than in front of independent witnesses.
Ontario courts distinguish undue influence from ordinary persuasion or family influence. A relative, caregiver, or beneficiary may discuss estate planning with a testator or express a preference without necessarily exercising undue influence. The legal issue is whether the pressure became so significant that the testator’s independent decision-making was overborne.
Ontario authority following the Supreme Court of Canada decision in Vout v. Hay treats undue influence as something that must be established by the party challenging the will. Ontario courts have described the required influence as sufficiently overpowering that the document reflects the will of the influencing person rather than the voluntary intentions of the deceased.
How is undue influence different from lack of testamentary capacity?
The two concepts are related but legally distinct.
A person may have testamentary capacity — meaning they are mentally capable of making a will — but still be subjected to undue influence. Capacity asks whether the testator was capable of understanding and making the decision. Undue influence asks whether the decision was actually made freely.
This distinction is important because vulnerability does not automatically mean incapacity, and dependency does not automatically prove undue influence.
For a closer comparison of the two issues, see Why do testamentary capacity and undue influence commonly arise in Ontario will challenges?.
What circumstances can raise concerns about undue influence?
ME Law’s existing estate-litigation material identifies situations involving pressure, coercion or manipulation of a vulnerable individual and disputes concerning whether a will, trust, or property transfer was made freely and with full understanding.
Potential concerns can arise where, for example, a testator becomes highly dependent on another person, is increasingly isolated from family members, or makes a significant estate-planning change in circumstances where a beneficiary exercises substantial control.
Those circumstances may justify investigation, but they do not by themselves prove undue influence. The surrounding evidence and the effect of the alleged influence on the testator’s decisions remain critical.
For more on ME Law’s work in this area, see Capacity & Undue Influence Litigation.
What happens if undue influence affected the will?
If undue influence is established, the validity of the affected testamentary disposition may be challenged before the Ontario Superior Court of Justice. Contentious estate proceedings can engage Rule 75 of the Rules of Civil Procedure, depending on the relief sought and the stage of the estate administration.
The broader grounds on which a will may be challenged are explained in What are the legal grounds for contesting a will in Ontario?.
The next question in this FAQ series addresses the separate issue of how undue influence can actually be proved, including the types of evidence that may become relevant.
Contact ME Law if you are concerned that pressure, manipulation, dependency, or control may have affected a will or other estate-planning decision.