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Testamentary Capacity

Last time I wrote about assessment of legal capacity, and emphasised the key point that capacity is not the same thing as cognition.

When a frail person wants to make an important decision, like sell a house, or appoint a Power of Attorney, the test for their capacity to do so is to interview them and assess whether they understand. Can he or she provide the details without being reminded? Are they internally logical? Can they foresee consequences and discuss options? Even if a person has cognitive impairment, they can retain capacity for specific tasks if they demonstrate adequate understanding of them.

In this edition, I focus on testamentary capacity. It is probably the most likely form of capacity assessment to get challenged years later in court and unfortunately it is potentially the hardest to get right. That is because it has its own specific requirements; merely saying you want to make a will and what might be in it is not enough.

Wills rely in the main on long-term memory, which can be retained well into the dementing process. It can be challenging to tease out what a person still knows when they are clearly incapacitated with day-to-day tasks, and answers may prove better than initial impressions suggested.

There is also a phenomenon of long-standing wills being changed when their maker approaches death, and scope for argument later about whether they were able to.

Against this background, it is necessary to tread warily. In 1870 a case in England called Banks v Goodfellow was brought to test the will of a man who had been known to suffer mental illness when he was alive. The judgement traversed a variety of earlier cases and arrived at a formula which continues to be good law today, a century and a half later and on the other side of the planet. There are four aspects to it.

Firstly, the person must be able to tell you what a will is.

Secondly, they must be able to tell you what their property is. Knowing every detail of their bank accounts is not called for. Few of us do. But a person must be able to independently state what their major assets are and get it right. It follows that doing this test means the doctor must get the details of the property from an independent source, usually the solicitor handling the legal side of things.

Thirdly, the person must know who has claims on their estate, which for practical purposes means their spouse and children. These are the people estates naturally pass to. Again, these details must be confirmed independently. Children from previous marriages, children who live overseas, children who do not regularly keep in touch, must all be known and accounted for. Even where a person wants to disinherit a child (which is not legally straightforward), they must make an active decision to do so. Children and spouses can’t simply be left out through failing memory.

Finally, a person must not be suffering any mental disorder which interferes with their testamentary decisions. It bears emphasis this does not mean they must be free of mental disorder entirely; just one that affects the will they are making. For practical purposes this means a delusion. So a person who wanted to dis-inherit a child because he wrongly believed the child was trying to poison him would not have testamentary capacity. A person who had a delusion on an unrelated subject would retain it.

Delusions are a useful illustration of the difference between cognition and capacity. A person with a delusion may retain normal understanding of the world in every other respect, but will not have capacity if the delusion colours their judgement.

Any assessment of testamentary capacity must therefore mention each of these four steps in turn, and what they patient was able to say about them.

In 2007 the BMJ ran an article co-authored by a psychiatrist and a solicitor on how to approach the task, [1] which remains essential reading, particularly as New Zealand’s Court of Appeal [2] subsequently endorsed it. As well as knowing the legal test, as above, the authors stress it is equally relevant to take practical steps like setting aside enough time and recording the patient’s answers verbatim. That record is what you will rely on later if your decision is challenged, which may well be years after the event.

As always, be sure the words you record are what the patient said. Recording that the patient nodded thoughtfully while you explained things, as per some assessments I have personally encountered, will not get you very far.

[1] Jacoby R and Steer P. How to assess capacity to make a will, BMJ 335:155 (2007) [2] Woodward v Smith [2009] NZCA 215


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