Patient capacity to consent

Health practitioners need a patient’s consent before providing medical treatment. Adults are presumed to have decision-making capacity unless there is evidence to the contrary.

Decision-making capacity

Under the Medical Treatment Planning and Decisions Act, a person has decision-making capacity if they are able to:

  • understand the information relevant to the decision and the effect of the decision
  • retain that information to the extent necessary to make that decision
  • use or weigh that information as part of the process of making the decision
  • communicate the decision and the person’s views and needs as to the decision in some way, including by speech, gestures or other means.

A person has decision-making capacity if they can make the decision with practicable and appropriate support.

Capacity is decision-specific. A person may have capacity for some decisions but not others.


  • It is the responsibility of the health practitioner to determine capacity for a specific decision.

  • You should not assume a person lacks decision-making capacity

    • on the basis of their appearance

    • because they are making a decision that others may consider unwise.

When a patient is likely to recover decision-making capacity

If the patient is likely to recover decision-making capacity within a reasonable time, you should wait for them to be able to make the decision - unless a further delay would result in a significant deterioration of their condition.

Downloadable Resources