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

Criminal justice and people with intellectual disability

Victims of crime

People with intellectual disability have been estimated to be up to 10 times more likely to be a victim of violent crime than other people.

Some laws include provisions that are important for people with intellectual disability, due to their understanding of relevant matters, and contexts where they are reliant on others for support. These are summarised below.

Family violence

Family violence intervention orders can be made under the Family Violence Protection Act 2008 (Vic), and can include orders against people who provide care for a person with disability, whether that care is paid or unpaid.

The types of acts contemplated include:

  • physical or sexual abuse;
  • emotional or psychological abuse;
  • economic abuse;
  • coercion or control and domination that makes the person fear for their safety and wellbeing.

Paid care can include supports funded by the NDIS (see Chapter 8.1: Understanding disability and the law) or in a residential service under the Disability Act 2006 (Vic).

Consent to sexual acts

While there is evidence of high rates of sexual assault of people with intellectual disabilities, reporting of these assaults has been low due to the reliance on others for support, and the repercussions when the abuser is providing this support. 

In this context, it is important to note these provisions in section 36 of the Crimes Act 1958 (Vic) (‘Crimes Act (Vic)’). A person is not considered to have consented to sexual act(s) where:

  • the person cannot understand the sexual nature of the act;
  • the person mistakenly believes the act is for medical or hygiene purposes;
  • the person does not say or do anything to indicate consent; or
  • the person submits because they are afraid of harm or force being applied to themselves or to someone else.

Further, there are specific offences in the Crimes Act (Vic) that cover a person who provides treatment or a support service (‘Provider’) to a person with intellectual disability (‘Client’):

  • It is a crime for a Provider to engage in acts involving sexual penetration with a Client (s 52B).
  • It is a crime for a Provider to engage in sexual touching with a Client (s 52C).
  • It is a crime for a Provider to engage in sexual activity in the presence of a Client (s 52D).
  • It is a crime for a Provider to cause a Client to be present when someone engages in sexual activity (s 52E).

Giving evidence

The prevention of abuse of people with intellectual disabilities has been hindered by difficulties with the requirements for a witness to give evidence. While the law assumes competence, many people with intellectual disability need support to be able to give evidence in court proceedings, and for their communication needs to be accommodated.

Some important protections apply to a witness with an intellectual disability:

  • A person with intellectual disability can simply use the words, ‘I promise to tell the truth’ rather than a full oath or affirmation when being sworn in as a witness (s 21(6) Evidence Act 2008 (Vic)).
  • A person with intellectual disability giving evidence about certain types of offences is allowed to give their evidence by audio or audio-visual recording rather than in a courtroom (s 367 Criminal Procedure Act 2009 (Vic) (‘CP Act’)).
  • Where a person with intellectual disability is the victim of an alleged sexual offence, all evidence must be given at a special hearing unless the person wishes otherwise. This includes them not being in the same room as the person accused of the offence when giving evidence, and only authorised people being present in the courtroom when evidence is given (s 370 CP Act). There are additional requirements about this type of witness being cross-examined or re-examined (s 376(1)).

Suspected or accused of committing a crime 

If the police suspect a person has committed a crime, they have the power to arrest them for questioning (see Chapter 3.5: Arrest, search, interrogation and your rights).

People with intellectual disability can experience disadvantage in this process due to limitations in learned behaviours and comprehension difficulties. For example, they may:

  • be more prone to suggestibility. When leading questions are used, they are more likely to agree to a proposition put to them, whether or not it is correct.
  • be eager to please a person perceived to be an authority figure. A police officer has a significant level of authority, and enthusiasm to give a positive impression can lead to giving the answers they believe the officer wants, and to conform with what they believe the officer expects them to say. Rather than admit to an absence of knowledge, they may give an answer that is confabulation or assumed to be the correct one.
  • have an incomplete or non-contextual understanding of what they are being asked, and poor insight into what is being implied, rather than stated outright.

Support and assistance

A person with intellectual disability being interviewed by police has a right to have an independent third person (ITP) present when being interviewed. The ITP should have a chance to talk to the person before they are interviewed, and the police officer should explain the person’s rights in plain language (see Chapter 8.3: Disability and criminal justice).

Under section 464D of the Crimes Act (Vic), a person who does not communicate in English (e.g. they communicate using Auslan or a communication tool) has the right to receive communication assistance during any police interview.

Alternative ways of dealing with criminal charges

State laws

Alternative ways of dealing with charges against a person with intellectual disability include:

  • supervision orders;
  • diversions;
  • justice plans;
  • consideration of special circumstances.

The provisions of the Crimes (Mental Impairment and Unfitness to be Tried) Act 1997 (Vic) provide mechanisms for dealing with people whose disability prevents them from understanding either the nature of the alleged offending, or the legal process itself (see Chapter 8.3: Disability and criminal justice).

Federal offences

Under section 20BQ of the Crimes Act 1914 (Cth), if a person charged with a crime has an intellectual disability, the court has the power to decide that it is more appropriate to:

  • dismiss the charge and release the person into the care of a responsible person (or require treatment) for up to three years; or
  • dismiss the charge and release the person unconditionally.

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