Undue influence

A will should always reflect the true wishes and intentions of the person making it (the ‘testator’). If pressure is put on a testator which ultimately causes them to make a will that doesn’t reflect their true wishes and intentions, it could amount to what we call ‘undue influence’. A will made as a result of undue influence is invalid and can be set aside.

What is undue influence?

Undue influence occurs when a person uses their power or authority to unfairly influence another person’s decisions.

The validity of a legal agreement or document can be affected by undue influence as it can deprive a person of their free will and consent. In some cases, undue influence can also amount to a criminal offence, such as fraud or abuse.

There are two types of undue influence: actual and presumed. See below for further information about each type.

What is actual undue influence?

Actual undue influence is when a person is subject to direct pressure or coercion by another. This might include threats, harassment or manipulation. If someone threatens to harm or blackmails another person into signing a document, for example, that would be actual undue influence.

In the context of wills, undue influence occurs when someone coerces or manipulates the testator into making or changing their will to benefit them, the influencer, or someone else, rather than representing the testator’s true wishes. Normal influence through close relationships, however, isn’t enough to overturn a will – it has to be undue influence sufficient to overcome the testator’s volition.

To prove actual undue influence, it must be shown that someone has actively coerced the testator into writing their will a certain way. Not all influences on a testator are necessarily undue; persuasion, feelings of gratitude for past services, or pity for someone’s economic circumstances can be valid and fair influences which a testator takes into account when deciding the terms of their will.

There’s no presumption of undue influence; actual undue influence has to be proved, and the person raising the allegation must prove that the influence was excessive, improper, or unconscionable. This can be very difficult, particularly where the person being undue influenced (such as a testator) has died. Setting aside a will on the grounds of actual undue influence is, therefore, not impossible but is far from straightforward.

What is presumed undue influence?

Where a relationship of ‘trust and confidence’ exists between parties, and the person in the dominant position takes advantage of the other’s vulnerability or dependence, a presumption of undue influence will arise. Relationships where ‘trust and confidence’ arises include a:

  1. Parent and child
  2. Doctor and patient
  3. Solicitor and client

The law presumes that the person in the dominant position may have taken advantage of the other person’s vulnerability or dependence. The person claiming to be influenced doesn’t need to prove the undue influence; they merely need to prove the existence of the relationship and that it was one of trust and confidence. The transaction should also call for explanation in the context of the relationship. It’s then for the person in the dominant position to disprove the presumption of undue influence by showing that the other person acted freely and independently.

In summary...


Actual undue influence

Presumed undue influence

Influence is based on:

The behaviour of the influencer.

The relationship of the parties.

Burden of proof:

The person who alleges undue influence must prove it.

It’s for the person in the dominant position to disprove the undue influence.

What are the effects of undue influence?

If undue influence is established, the transaction affected can be set aside. The effects of undue influence depend on the nature and circumstances of the case but, generally, a will that’s tainted by undue influence can be set aside by the court, and the parties can be restored to their original position. This may not be possible if a third party has acquired rights or interests in good faith. In such cases, the person who suffered undue influence may seek other remedies (such as damages, injunctions, or rescission).

Our content explained

Every piece of content we create is correct on the date it’s published but please don’t rely on it as legal advice. If you’d like to speak to us about your own legal requirements, please contact one of our expert lawyers.

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