When you or a loved one makes or changes a Will, you need to make sure that you have testamentary capacity – in other words, the law must consider you mentally capable of doing so.

If someone makes or changes a Will without testamentary capacity, their Will is considered invalid, and their estate could be distributed in a way that doesn’t match their wishes.

In this article, we’ll explore what testamentary capacity is, how it works in Victoria, and how meeting testamentary capacity criteria reduces the likelihood of your Will being challenged after you die.


  1. Presumption of Testamentary Capacity
  2. Validity of a Will: Based on Balance of Probabilities
  3. Test for Testamentary Capacity
  4. Assessing a Testator’s Capacity
    1. Solicitors
    2. Medical Practitioners
  5. Freely and Voluntarily
  6. Contact Us

Presumption of Testamentary Capacity

If a Will is “rational on its face and duly executed, there is a presumption that the deceased had testamentary capacity”, or power to make a Will, at the time of signing the Will. However, the force of this presumption is reduced if there are circumstances that suggest the testator may have lacked testamentary capacity at the time of signing.

Validity of a Will: Based on Balance of Probabilities

To satisfy the Court that the relevant Will is valid, a person must prove on the balance of probabilities that, at the time of executing the Will, the testator had testamentary capacity.

Test for Testamentary Capacity

The test for determining whether a testator had testamentary capacity is set out by Lord Cockburn CJ in Banks v Goodfellow.  The test is that a “testator:

  • Shall understand the nature of the act and its effects;
  • Shall understand the extent of the property of which he is disposing;
  • Shall be able to comprehend and appreciate the claims to which he ought to give effect; and
  • With a view to the latter object, that no disorder of the mind shall poison his affects, pervert his sense of right, or prevent the exercise of his natural faculties – that no insane delusions shall influence his will in disposing of his property and bring about a disposal of it which, if the mind had been sound, would not have been made.”

Assessing a Testator’s Capacity


A solicitor taking instructions for a Will has a duty to ensure that the person giving the instructions has testamentary capacity and is giving the instructions freely and voluntarily.  To carry out that duty, solicitors must:

  • take reasonable steps to ensure testamentary capacity; and
  • provide reasons for any conclusions.

When drafting a Will, if there is any possibility that the testator’s capacity could later be questioned, a solicitor must ask relevant questions to establish whether the requirements for testamentary capacity, as set out in Banks v Goodfellow, have been satisfied.

In the case of testators who are elderly, who have complicating medical histories, and/or who have proposed substantial changes in the disposition of their assets under a new Will, solicitors should arrange for the testator to be assessed for testamentary capacity by a proficient medical practitioner before signing the Will.  This will ensure a medical opinion is provided for any medical conditions the testator may have and whether these conditions may impact the testator’s testamentary capacity.

When considering testamentary capacity, the Court may request evidence of the steps solicitors took to determine the testator’s testamentary capacity. According to Bailey v Maddock, the weight given to the solicitor’s evidence will depend on:

  • “his or her experience, training and understanding of the test of testamentary capacity;
  • his or her ability to make an assessment of capacity taken with the quality of the assessment made as appears from any contemporaneous notes and records;
  • his or her knowledge of and familiarity with the will-maker, including the age and state of health of the willmaker;
  • his or her independence;
  • the will-maker’s presentation to the solicitor;
  • whether there are any ‘red flags’ suggesting a possible challenge to capacity”, and
  • “the level of enquiry and discussion on the part of the lawyer of and with the deceased”.

It is important to note that testamentary capacity should not be assessed over the phone, particularly where complicating health, age and cognitive issues exist.

Medical Practitioners

According to Bailey v Maddock, when assessing testamentary capacity, medical practitioners must:

  • address each element of the test for testamentary capacity, providing reasons for each conclusion made;
  • explain how their relevant consultation on a particular date allowed them to be able to conclude that the deceased had testamentary capacity on that date; and

consider how the deceased’s recent medical history may have impacted their testamentary capacity.

Freely and Voluntarily

When drafting a Will, a solicitor must also ensure that the person giving instructions is doing so freely and voluntarily.  A face-to-face appointment is necessary in these circumstances so a solicitor can ensure the client is alone when giving instructions and is not being pressured by someone else in the room.

Solicitors should be suspicious of the involvement of a beneficiary where a new Will is being proposed with a substantial change for the benefit of that beneficiary.  In these cases, solicitors should obtain information about any recent, heavy reliance on a beneficiary to whom the substantial change would benefit significantly or disproportionately.

The free and voluntary signing of a Will may be unable to be established where the beneficiary was “heavily involved with the deceased in circumstances where the deceased was likely to be vulnerable or impressionable as a result of his circumstances and became dependent on the beneficiary”.

Examples may include where a beneficiary held the power of attorney, witnessed the Will, took the testator to make changes to the Will, was present during the testator’s meetings with their lawyer regarding any Will changes, and so on.

Contact Us

If you would like to create or update your Will to properly protect your interests and reduce the likelihood that your Will could be successfully challenged, or challenge a Will that you believe is not rational and/or may not have been properly executed, contact our experienced team at Pentana Stanton Lawyers on (03) 9002 2800.