There are many degrees of intellectual disability. The definitions and accepted diagnostic test for determining whether or not a person has an intellectual disability are explained along with key legislation. It is vital that each person’s case be assessed individually, and that the views of the person who has an intellectual disability always be sought, taken into account and, wherever possible, acted upon. All people with Autism Spectrum Disorders can now be considered for disability services.


Naomi Anderson

Principal Solicitor, Villamanta Disability Rights Legal Service

Civil law and people with intellectual disability

Capacity to make decisions

The law presumes that people over the age of 18 have the capacity to make (and live with the consequences of) their own decisions.

People with intellectual disability often experience difficulties with this presumption in two ways:

  • Their right to make their own decisions (and mistakes) is ignored, and other people are allowed to make decisions for them.
  • Their need for support to understand the implications of important decisions is overlooked or purposely exploited.

It is equally important for people with intellectual disability to be free to make their own choices as human beings (e.g. to vote, to decide who they have a relationship with, whether they will marry, or become a parent, where to live, what employment or hobbies to pursue, what to buy, how to spend their time, what they want to happen to their possessions after they die, what medical treatment they want, and how they want end-of-life decisions to be made) and to be protected from people who would cause them harm by pushing them into choices they don’t fully understand.

The challenge that many people with intellectual disability face relates to a misunderstanding of the presumption of capacity, when:

  • people overcomplicate the level of understanding needed to make everyday decisions. For example, why should a person with intellectual disability have a more detailed knowledge of the policies of every candidate for an election than other voters? Why should they need to understand absolutely every potential implication of entering into a relationship, when nobody else has to do that?
  • people take advantage of people with an intellectual disability’s need to have information explained in a way they can understand, exploit them, and undermine their confidence. Most people assume a level of legal literacy and consumer protection to choose to agree to some things without questioning and be suspicious of others. We make these decisions based on both experience of other similar transactions, and our confidence in the person proposing it. Many people with intellectual disability have had few chances to make their own decisions and have a very limited social circle. They can be coaxed to agree to things that do not benefit them at all, solely because the person suggesting it is a ‘friend’. The desire to be seen as a competent person capable of making their own decisions – when their decision-making rights are constantly challenged by others – can create this vulnerability.

Important rights and protections for people with intellectual disability are summarised below.

Signing a contract

Adults are presumed to have capacity to enter into a contract with another person. Unless a person is subject to an administration order (see Chapter 8.6: Guardianship and medical treatment), the other party to the contract can assume the person has capacity, within the constraints of the relevant consumer law and financial regulations.

People with intellectual disability may need support when making decisions, including entering into contracts. This does not mean they can’t enter into contracts, just that they may need some additional assistance to:

  • understand what the contract is about, and what the terms mean;
  • understand their choices and that they do not have to sign a contract they don’t agree with;
  • make sure the contract is beneficial to them, and will meet their needs;
  • understand what they can do if they have a problem after they have signed the contract.

Consumer rights apply to people with intellectual disability. It is unlawful for a business to take advantage of a person with intellectual disability by:

  • creating undue pressure on the person to sign a contract, or agree to terms they do not understand;
  • not making sure they understand the terms of the agreement;
  • signing someone up to a loan that is not suitable for their needs, or that they can’t pay.

NDIS and engaging service providers

The NDIS allows participants to choose their own service providers for their disability supports, and generally these arrangements are written in a service agreement.

The Australian Competition and Consumer Commission (ACCC) has published important information to help people understand their rights when entering into these agreements (see the ACCC’s website).

Being a parent

Parents with intellectual disability have interaction with the child protection system at a far higher rate than other parents. While the child protection system has a responsibility to ensure the safety of children, it is sometimes discriminatory against parents with intellectual disability and is not always good at understanding the supports available.

The Independent Family Advocacy and Support program run by Victoria Legal Aid can assist parents with intellectual disability who have had contact from the child protection system.

Supported decision-making

We all need help making important decisions. We talk to family and friends, we ask for expert advice, we look up things on the internet.

For people with an intellectual disability, some decisions have complex implications that can be difficult to grasp, so having a more formal way of being supported to make those decisions is helpful.

Informal arrangements

A person with intellectual disability may have an informal arrangement with a family member or friend, where they are supported to make decisions and manage their affairs. Informal arrangements might be with an individual, a number of close family members, or with a circle of support people, and may be a practical and positive way of supporting the person to have choice in their life without other restrictions put in place.

However, the high rate of abuse of people with intellectual disability means that it is important to ensure that these arrangements:

  • are voluntary – if a person has others involved in making decisions for them without their consent, there is a danger that this is an abusive arrangement;
  • are transparent – having a circle of support people ensures that others are involved to keep the wishes of the person as a focus, whereas an arrangement with a friend who does not disclose the details may be more open to abuse over time;
  • are beneficial – having a family member help with finances can be great, but if the person with intellectual disability finds themselves without money for important things, the arrangement may not be right for them, and in some cases might be financially abusive;
  • are flexible – a young adult with intellectual disability may be happy for their parent to handle their finances and make some decisions for them, but as they increase their skills, they may wish to have more control of these choices. An informal arrangement that does not allow for the person to take back control is not voluntary.

Supportive power of attorney

A person with intellectual disability can choose to appoint a supportive power of attorney who can gather information for them and assist them with making important decisions. If they have the capacity to make such an appointment, they also have the capacity to revoke it if they change their mind. A supportive power of attorney does not have the authority to make decisions for the person (see Chapter 8.7: Understanding powers of attorney).

Supportive guardians and administrators

VCAT can appoint supportive guardians and administrators if this is beneficial to the person with intellectual disability (see Chapter 8.6: Guardianship and medical treatment).


Both Centrelink and the National Disability Insurance Agency (NDIA) have provisions for a nominee to be appointed for a person with intellectual disability. 

In the case of Centrelink, a nominee can only be appointed by:

  • the person with intellectual disability, by signing a form authorising the nominee;
  • a court, tribunal or by guardianship or administration order.

In the case of the NDIA, a nominee can be appointed by:

  • the NDIS participant; or
  • the NDIA.

It is important to remember that there are significant limitations on an NDIS nominee’s powers to make decisions for the participant (see Chapter 8.1: Understanding disability and the law).

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