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Capacity and cognition assessments - What’s the difference and why is it important? - by Dr Roderick

New Zealand’s ever ageing population is an ongoing source of challenges for the medical profession, and the assessment of legal capacity is an issue that doesn’t get as much attention as it should.

New Zealand’s ever ageing population is an ongoing source of challenges for the medical profession, and the assessment of legal capacity is an issue that doesn’t get as much attention as it should.

People in their latter years often need to sell property, enter retirement villages, make wills, drive their cars and appoint relatives with Power of Attorney to act for them. A question that often arises is whether a person who has become frail can still make such decisions. Not only do these decisions have obvious implications for their welfare, but they can be challenged. Relatives who are unhappy with their allocation in a will or their sibling being appointed as Power of Attorney instead of themselves can instruct their own lawyers to deal with the matter. Doctors who made the capacity assessment are often an obvious target.

Any doctor who has made a capacity assessment can anticipate it may be legally challenged, including years afterwards. I have been in this position and have been informed that another outing on the same theme is due in the Auckland High Court next February. Getting things right at the outset is desirable.

So how should capacity be assessed?

One of the enduring myths is that capacity is the same thing as cognition. In fact, this is wrong. It must be firmly underlined that capacity and cognition are not the same thing, and cognition assessments do not answer the capacity question.

A person with normal cognition can lack capacity and a person with cognitive deficits can retain it, particularly for decisions that require long term knowledge, like making a will.

The key point about capacity is that it turns on a specific question. People with advanced cognitive deficits like dementia can safely be judged as lacking capacity for all significant decisions, but these are not the ones that cause the diagnostic difficulty, or the litigation. The challenge is the person who has early cognitive decline, as sorting what they can still be trusted to do.

So the person seeking the capacity assessment, often the family lawyer, needs to specify exactly what is being sought. Sometimes the patient will have instructed them directly, and sometimes family will be doing it on the patient’s behalf. But in all cases the party seeking the assessment needs to specify exactly what is proposed.

The assessment turns on interviewing the patient, without any family or advisers present, (nor with them being in the room any time recently), and finding out what they have got to say. The test is whether the patient can describe in their own words what they want to do, and get the details right.

A person seeking to sell a house needs to be able to say so without prompting. They need to know what house they are referring to and some details like why they want to sell it and what is involved. They should, for instance, have a basic idea of what it means to engage a real estate agent.

It is vital that the patient supplies the details. Yes and no answers are of little use at the best of times, but entirely so when the point is to test understanding. People with cognitive impairment usually go to trouble to conceal it. They lose their caution around committing themselves to things they no longer understand and place weight on emphasising that all is well. People in that situation will routinely agree with what is being put to them, then be unable to say anything relevant when pressed for further details.

A person who has been talking to family or their lawyer in the previous fortnight about selling their house should be able to volunteer that information in response to a broad question like “ I understand you want to make a significant decision about your legal affairs. Can you tell me what that is?” If they cannot respond with the right issue then you have a problem.

Understanding needs to be broad brush. A person who has their house in a family trust needs to be able to volunteer that, but does not need to know the legal definition for what a trust is.

Capacity varies depending on how complex the issue is. A person might well be able to pass the test for the routine sale of a family home but not for unwinding business assets in complex legal structures. They might be able to describe their wishes for a simple will (one house, two children, half each), but not for a complicated one. Everything comes down to specifying exactly what is proposed and whether the patient can describe it in a way that the doctor finds convincing. There is no medical magic to it. The yardstick is a common-sense approach to whether people seem to know what they are talking about.

It is relevant to note whether you suspect a person might feel unduly pressured. It is also relevant if a person has delusional beliefs that color their thinking. This is particularly relevant for wills, which will be the subject of the next article. These are examples, as mentioned above, where a person may have normal cognition but lack capacity because their thinking is affected by factors other than understanding.

Nothing turns on whether the arrangements are desirable. There may be good reasons for a devoted daughter to become a Power of Attorney or a family business to be resettled on children or a home to be sold for rest homes fees, but none of this affects the capacity decision. No matter how useful the action would be, the person still has to meet the test of knowing what is going on. There is legal work known to the lawyers if a person lacks capacity; the test should never be stretched to rescue the position.

It is desirable to devote proper time to the interview and not squeeze it in on a busy day. In an aged-care facility, consider having the senior nurse present. Remember impaired people are usually at their best at the start of the day.

If a person seems to be borderline, consider any intercurrent illness. Simple conditions like urinary infection and constipation can make a dramatic difference to cognition in the frail. Consider doing it more than once and consider getting a colleague to provide an opinion as well.

Provide the lawyer with a proper statement, for your sake as well as theirs. State your qualifications and experience. State the questions you asked and what the answers were, because if you are challenged later that is the detail you will need to defend your decision.

Above all else, record the capacity question you were answering. It can make a big difference. The writer’s outing in the High Court next February comes down to a solicitor, years ago, taking a more liberal view of what the patient was judged to be capable of than the doctor’s letter said. It concerns a will, and wills have their own special requirements. Of that more next time.


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