doctor with elderly man and his daughter

Determining testamentary capacity

The legal test for testamentary capacity (capacity to make a will) is different from the test for capacity to make healthcare decisions. It is important to be aware of the differences and your responsibilities if you are asked to assess testamentary capacity.

Tuesday, 23 April 2024

Quick guide

  • Testamentary capacity refers to the capacity to make a will. This is different from the capacity to make healthcare decisions.
  • Testamentary capacity is determined by a lawyer; however, you may be asked by a lawyer or a patient directly to assess the patient’s cognitive abilities as part of this process.
  • A simple mini-mental state examination is not sufficient to assess capacity for this purpose.  Capacity does not equal a score on the mini-mental state examination.
  • If you have any doubt about your experience or skills to assess a patient’s capacity, refer them to an appropriate specialist who is comfortable performing such assessments such as a geriatrician, psychogeriatrician or neuropsychologist.

In a general sense capacity is a person’s ability to make decisions for themselves. Capacity is decision and situation specific so a person may have the capacity for some decisions and not others, or in some situations such as the time of the day for example and not others. This factsheet focuses on your role if you have been asked to assess testamentary capacity.

Differences between capacity for health care decision-making and testamentary capacity

Capacity to make healthcare decisions Testamentary capacity 

A person has capacity to make a healthcare decision if they are able to understand the nature and consequences of the decision to be made. A person must also be able to communicate their decision, verbally or by other means. 

  • Understand: the information and consequences relevant to the decision.
  • Retain: Hold the information and recall the details for long enough to make the decision.
  • Weigh: Use and evaluate the information throughout the decision-making process.
  • Communicate: Relay their decision and understanding.

For more information on capacity healthcare decisions refer to our factsheet Capacity - the essentials 

The person making the will must be able to:

  • be aware of and appreciate the significance of the act which they are undertaking
  • be aware in general terms of the character, extent, and value of their estate
  • be aware of those who might reasonably be thought to have claims upon their estate, and the basis for and nature of those claims
  • be able to evaluate and discriminate between the respective strengths of those claims.

The person must also not be affected by any 'disease or disorder of the mind'.

What is your role?

As a patient’s treating doctor, you may receive a request from a lawyer for your opinion about whether your patient currently has testamentary capacity, or a request about whether your now deceased patient had capacity at the time they made a will.

Current patient 

Your role is to provide an opinion about the patient’s cognitive abilities, which the lawyer will rely on to be satisfied of your patient’s capacity to make a will. Ultimately it is the lawyer’s role to determine if the person has testamentary capacity factoring in any medical opinions.

If you do not feel you have the skills or experience to assess your patient’s cognitive ability for this purpose, you are under no obligation to do so. In this situation you could refer the patient to an appropriate specialist such as a geriatrician, psychogeriatrician or neuropsychologist for the assessment.

If you do feel comfortable doing the assessment, there are various aspects that you need to cover.  Conducting a simple mini-mental state examination of your patient is not sufficient.

If a lawyer requests your opinion on a patient’s testamentary capacity they should provide you with the following information:

  • the person’s relevant background and history including personal circumstances
  • financial circumstances and any relevant legal proceedings
  • relevant details of the legal test for testamentary capacity.

You cannot complete an assessment of testamentary capacity without this information, and if you do not have it, you should request it.

The assessment

An assessment of a patient’s testamentary capacity involves a consideration of the following:

  • whether the person is suffering any condition that may affect cognition and if so, what it is, and
  • if in your opinion the extent of the cognitive impairment is such that the person is not:
      • aware of the nature and effect of a will
      • aware of the nature and extent of their assets (even if only in a general sense)
      • able to assess who are their natural beneficiaries, such as family and personal friends
      • able to understand their obligations to provide for people who are dependent on them
      • able to discriminate between the strengths of the claims of potential beneficiaries
      • able to understand the consequences of their decisions about who they will benefit.

You can explore the patient’s understanding of these issues by integrating this information into a conversation and asking questions such as:

Who is in your family?

What assets do you have?

Who are you planning to benefit from your estate?

If they are omitting a family member, can they explain their reasoning?

The report

You should send back a report to the lawyer that includes your title, experience and how long you have known the patient. Include the information above and anything else you may consider relevant.

Consider the following hypothetical report

Dr C Baxter FRACGP

Geelong Medical Centre 


I am Dr Christopher Baxter from Geelong Medical Centre where I have been a practising general practitioner since my graduation from Monash University in 1999.

I can confirm that Ms Ruby Smyth from 24 Donald Street Geelong has been a patient of this clinic since 2006. Ms Smyth's medical history is attached. She was diagnosed with dementia in 2019 by myself, and confirmed with a geriatrician shortly thereafter. She currently has some limitations with her short-term memory and social behaviours.  

Despite these challenges, she was able to describe to me in detail the specifics of her immediate family, identifying all her children, their partners and grandchildren. She could outline the general nature of her estate and assets and her desire for these assets to be split between her four grandchildren evenly.  Ms Smyth had a reasonable idea of the specifics of her wishes and the implications for all her immediate family. Although she did forget some specifics in relation to her superannuation and bank details, and despite her diagnosis of dementia it is my opinion that she has sufficient capacity to sign her will and understand the implications of doing so. 

Yours sincerely

Dr Baxter

Deceased patient

You may be approached by a lawyer or a deceased patient’s family member for your opinion about whether your deceased patient had capacity to make a will at some earlier time. Before responding, confirm that the requesting party has the appropriate authority so that you can disclose the patient’s information to them. Your duty of confidentiality continues after the death of the patient. See Avant factsheet: Deceased patients and their medical records.

Whether you can provide an opinion will depend on whether you had assessed the person’s cognitive abilities around the time they made a will and whether you have documentation to support your opinion.

Be extremely cautious about making any statement about a deceased patient’s capacity retrospectively – it is very difficult to carry out a retrospective assessment of testamentary capacity.

You may have information in your medical records about whether the patient had a relevant diagnosis or a cognitive impairment at the time they made a will that might have impacted on their ability to do so.  Alternatively, you may have no information that suggests the patient was suffering any cognitive impairment at the time.  

You have no obligation to assist if you do not feel comfortable doing so or feel that it is outside your skills and experience.

Consider the following hypothetical report

Dr D Jones

Highgate Medical Centre


I am Dr David Jones from Highgate Medical Centre where I have been practising general practitioner since my graduation from Melbourne University in 1999.

I can confirm that Mrs Jane MacDonald from 24 John street, South Point DOB 03/03/42 was a patient of this clinic for more than 20 years until her death 13/09/22.

I have been asked to provide an opinion as to Mrs MacDonald's testamentary capacity as of 23/04/22 when she signed her will. 

Unfortunately, I am unable to do so as this is a specific legal test rather than a medical diagnosis, and no historical assessment of testamentary capacity was undertaken.

I can confirm the medical history as attached, including:

  • Hypertension 80mg Telmisartan
  • Hypercholesterolemia 10mg Rosuvastatin
  • Diabetes (NIDDM) 1000mg Metformin

20/08/2020 Geriatrician referral with a cognitive assessment undertaken and no signs of impairment reported.

11/07/22 Routine appointment and blood tests at this clinic. My medical notes state Mrs MacDonald appeared well with no complaints.

Mrs MacDonald appeared to be alert and well-informed at all times during my interactions with her. However, I am unable to comment any further on her capacity. 

Yours Sincerely 

Dr Jones

Pre-prepared affidavits 

You may be contacted by a lawyer asking you to sign a draft affidavit saying the patient has testamentary capacity.

You need to undertake your own assessment of the patient and complete any affidavit based on that assessment.  Do not sign any pre-prepared affidavit unless your assessment of the patient is in total agreement with what has been provided.

More information

For medico-legal advice, please contact us on or call 1800 128 268, 24/7 in emergencies.


This publication is not comprehensive and does not constitute legal or medical advice. You should seek legal or other professional advice before relying on any content, and practise proper clinical decision making with regard to the individual circumstances. Persons implementing any recommendations contained in this publication must exercise their own independent skill or judgement or seek appropriate professional advice relevant to their own particular practice. Compliance with any recommendations will not in any way guarantee discharge of the duty of care owed to patients and others coming into contact with the health professional or practice. Avant is not responsible to you or anyone else for any loss suffered in connection with the use of this information. Information is only current at the date initially published.

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