Undue Influence in a Will

Persuasion is not undue influence. Coercion is. The distinction is what these cases turn on, and it is proved almost entirely on circumstantial evidence.

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Undue InfluenceWill ChallengesSuspicious CircumstancesEstate Litigation

Influence becomes undue when the testator's own volition is overborne.

The Short Answer

What counts as undue influence?

Conduct amounting to coercion, where the testator's own volition is overborne so that the will expresses someone else's wishes rather than their own. Persuasion, argument, appeals to affection and even persistent pressure are generally not enough. The person alleging it bears the burden of proving it, and it is almost always proved circumstantially.

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THE THRESHOLD

Persuasion Is Not Undue Influence

Families influence each other. A child who spends more time with a parent, who is more attentive, who makes their views known, is not thereby exerting undue influence, even if the will reflects that relationship.

The threshold is coercion. The question is whether the testator's own volition was overborne, so that the document records another person's wishes rather than theirs.

That is a demanding standard, and it is why unfairness alone never succeeds. A will that treats children unequally is not evidence of coercion; it is evidence of a decision.

THE EVIDENCE

Proved Almost Always Circumstantially

Coercion rarely happens in front of witnesses. These cases are built from surrounding circumstances:

The testator's vulnerability, through age, illness, dependence or isolation.
The opportunity the alleged influencer had, particularly where they controlled access.
Their involvement in the will's preparation, including instructing the solicitor or being present.
A significant and unexplained departure from a previous will or from long-stated intentions.
The absence of independent legal advice.
A benefit that is disproportionate to the relationship.

No single factor decides it. What persuades is a pattern where each element supports the others.

SUSPICIOUS CIRCUMSTANCES

How the Burden Can Shift

This is a related doctrine and it is frequently the more useful one.

Normally a properly executed will is presumed valid and the challenger must displace that presumption. But where suspicious circumstances are shown, the burden can shift back to the person propounding the will to prove that the testator knew and approved its contents and had capacity.

Circumstances that attract this include a major beneficiary arranging the will or instructing the lawyer, a significant change made shortly before death, a frail or isolated testator, and preparation without independent legal advice.

Establishing suspicious circumstances is often the strategic objective early in a challenge, because the shift in burden changes the case substantially.

REALISM

What These Cases Actually Cost

Undue influence is among the harder allegations to prove, and the assumption that estate litigation costs come out of the estate has narrowed considerably. Courts now more often apply ordinary costs principles, meaning an unsuccessful challenger can be ordered to pay the other side's costs personally.

The estate is also frozen while the dispute continues. Where the main asset is a house, it may sit unsold, incurring costs, for the duration.

Mediation resolves a high proportion of estate disputes and is worth attempting early. Part of an honest assessment is whether the claim is strong enough to run, and sometimes it is not.

General information

This page is general information about Ontario and Canadian law published by Lexaltico LLP. It is not legal advice, it does not account for the facts of any particular situation, and reading it does not create a solicitor-client relationship. Rules change, and whether any option is available to you depends on your own circumstances.

Elder and vulnerable persons

Common Questions

Frequently Asked Questions

Is it enough that my sibling was always there?

Presence and opportunity are relevant but not sufficient. The case needs evidence pointing to coercion rather than closeness.

Can I challenge because the will is unfair?

Unfairness is not a ground. It may be evidence supporting another ground, but it does not stand alone.

What is the difference from lack of capacity?

Capacity concerns whether the testator was able to make a will. Undue influence concerns whether the will they made was actually theirs. They are often pleaded together.

How long do I have to bring a challenge?

Time limits apply and differ by claim type. Dependant support in particular has a short period tied to the certificate. Delay is the enemy of every one of them.

Who pays if I lose?

Potentially you. Costs increasingly follow the ordinary rules rather than being borne by the estate.

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