What is impaired decision-making capacity?

'Impaired decision-making capacity’ is a term that can cause confusion because a person’s decision-making capacity relates to specific situations and is not a general state of being.

Everybody has the right to make decisions that affect their life. It’s a basic human right and it’s how we live our lives independently. The law presumes every adult has the capacity to make their own decisions, which means you can’t assume someone has impaired capacity without sufficient evidence.

So how do we know if someone has lost their ability to make their own decisions?

What is the formal definition of capacity?

The Guardianship and Administration Act 2000 and Powers of Attorney Act 1998 define capacity as the ability to:

  1. understand the nature and effect of decisions about a matter
  2. freely and voluntarily make decisions about the matter and
  3. communicate the decisions in some way.

So let’s have a closer look at what that means in practice.

Understand the nature and effect of a decision about a matter
This means that a person can understand everything that needs to be considered when making a decision, what the possible choices are, and what the potential consequences and outcomes of those choices could be.

Freely and voluntarily make decisions about the matter
The most common example of an adult being unable to make a decision freely and voluntarily is where an adult is being influenced by friends or family to make a decision. This may be evident when the adult seems to be making decisions you would not expect them to make if they were making that decision independently, especially when that decision might not be in their best interest. An example of this could be selling their house to a friend or relative for less than market value.

Communicate the decision in some way
It’s important to remember that communication isn’t limited to just verbal communication, i.e. just because someone isn’t able to speak doesn’t mean they don’t have capacity. For example, they may communicate through writing, storyboards or through signals to indicate yes, no or letters of the alphabet. Capacity is only lacking if the adult isn’t able to communicate the decision in any way.

If an adult can’t do at least of one of these things regarding a decision, they do not have the capacity to make that decision.

Some important points about capacity

An adult can have capacity to make decisions about some thing but not others
Someone can have the ability to make decisions about relatively simple things such as what to buy for dinner but not for more complicated issues such as taking out a new internet plan or consenting to have surgery.

Physical appearance isn’t an indication of loss of capacity
Just because someone is old, disabled or simply dishevelled, it doesn’t automatically mean they have lost capacity. Similarly, factors such as anxiety, medication, drugs and alcohol can sometimes make it look like someone has lost capacity but this may not be the case.

Unwise choices aren't necessarily a sign of loss of capacity
We may not like someone’s decision, or think it’s risky or reckless but it doesn’t mean they lack capacity. A person has the right to make a decision we don’t agree with; after all, we all make bad choices and decisions from time to time.

Loss of capacity isn't necessarily permanent
Capacity can fluctuate over time. For example, a person may be unwell due to illness but recover completely. While they are sick, they might have been unable to make decisions but, once recovered, they may be fully able to manage their own affairs again. This is why a person’s past ability should not lead anyone to assume they lack capacity right now.

Who can clarify someone's capacity?

If you are unsure about whether an adult has impaired capacity for a particular matter, an assessment by a health professional such as a general practitioner, geriatrician, neuropsychologist or psychiatrist can be helpful to obtain an informed opinion about the adult’s capacity.

Sometimes there is a dispute about capacity. This can happen in family conflict situations or there may be conflicting opinions or a need for a formal determination about an adult’s capacity due to various important decisions being required. Only the Queensland Civil and Administrative Tribunal (QCAT), or the Supreme Court of Queensland, can formally determine an adult’s decision-making capacity. This will be done at a hearing where a wide range of evidence will be given, including from the adult, other parties and any reports/information from health professionals involved with the adult.

Please note, OPG has no legal authority to make a formal declaration an adult’s capacity.