Last updated 15 February 2019

A person with a disability may become involved with the criminal justice system as a victim of crime, as a person accused of a crime or as a witness. In all of these cases, the capacity of the person to give evidence may arise as an issue.

People with disabilities as witnesses

A person is only able to give evidence in court if they are considered competent to do so.

Every person is presumed to be competent to act as a witness unless it is demonstrated to the judge that they are not.

In general, to be a competent witness, a person must be able to understand the nature of the oath and have sufficient memory and capacity to express their memory. In considering whether or not a person is competent as a witness, a court will consider whether the witness’s disability will affect the reliability of evidence on the facts of the particular case. Considerations may be a witness’s capacity for observation, their ability to recollect what happened, or whether it is possible to know if what they say is in any way related to real experience.

In Queensland, a person who is not considered by the judge to be competent to take an oath may give unsworn evidence. The judge must be satisfied the person understands that the truth must be told and they may be punished if the truth is not told.

Special witness provisions

Appearing before a court as a witness can be an intimidating experience. For some people with a disability, this prospect may be sufficient to discourage them from following a complaint through to court. However, special arrangements can be made to make a person who has a disability feel more comfortable in court.

Under pt 2 div 4 of the Evidence Act 1977 (Qld), a court can make exceptions to the normal mode of giving evidence for a special witness. A special witness is a person who, if required to give evidence in accordance with the usual rules and practice of the court, would:

  • as a result of intellectual impairment or cultural differences be likely to be disadvantaged as a witness
  • be likely to suffer severe emotional trauma
  • be likely to be so intimidated as to be disadvantaged as a witness.

The orders that the court may make are:

  • in criminal proceedings, to exclude the person charged from the court room or obscure them from the view of the special witness, while the special witness is giving evidence or is in court for any other purpose
  • to exclude all persons other than those nominated by the court from the court room
  • to order that the special witness give evidence in a room other than the court room, and from which all persons other than those nominated are excluded
  • to approve a particular person to be present while the special witness is giving evidence or is required to appear in court for any purpose, in order to provide emotional support to the special witness
  • to order that a videorecording of the evidence of the special witness be made, and that the videorecorded evidence be viewed and heard in the proceedings instead of direct testimony.

People with disabilities as victims

According to the law, a person with a disability who is a victim of crime has the same rights to the protection and assistance of the law as any other person. Often it does not work this way.

Many factors can cause the less favourable treatment of a person with a disability. A victim with an intellectual or psychiatric disability may be less likely to complain about an infringement of legal rights. Even when a person with a disability does manage to contact police or someone does on their behalf, police may decide not to prosecute because they feel the person with a disability will not be a good or reliable witness.

People with disabilities as offenders

Some criminal acts (e.g. murder) require that the person committing the offence had the intention to commit it (or to commit the act that led to the offence). Some people with a disability may be incapable of forming an intention to commit a crime due to their disability. Other criminal acts (e.g. assault) do not require that the person committing the offence had any such intention. However, even in these cases, a person with a disability may not be criminally responsible for an act where they could not understand what they were doing.

Support person

In Queensland, when police interview a person with impaired capacity, they are required to have a support person (independent person) present. The support person may be a parent or friend of the person with a disability. People with a disability are also entitled, before they are questioned, to speak with a support person without being overheard. Moreover, if it becomes apparent to police that a person they have charged has a disability, police must suspend questioning until they have allowed the person to speak with a support person (s 422 Police Powers and Responsibilities Act 2000 (Qld) (PPR Act)).


A person with a hearing impairment is entitled to have both an interpreter and an independent person present during the interview. Under both the Crimes Act 1914 (Cth) and the PPR Act , federal and Queensland police officers investigating a case must arrange for an interpreter to be present, if they believe that the person under arrest is unable to communicate verbally in English, due to a physical disability or inadequate knowledge of the English language.

Consequences of unfair treatment

Police are legally bound to follow the requirements outlined above. A failure to comply with them may result in the officers being personally penalised. In addition, any confession obtained in an interview in which these procedures have not been followed may be inadmissible as evidence.

When doubt exists about the fairness of an interrogation of a person with a disability or the voluntariness of a confession, an application should be made to the court to exclude such evidence.


The two defences most commonly pleaded by people with a severe or profound intellectual or psychiatric disability are insanity and diminished responsibility.

Insanity is a complete defence, leading to a finding of not guilty. Someone who is found not guilty in this way may still be detained in an institution (ss 27, 647 Criminal Code Act 1899 (Qld) (Criminal Code)).

The defence of diminished responsibility is only available in Queensland for murder charges to reduce the charge to manslaughter (s 304A Criminal Code).

These and similar matters are also dealt with under the Mental Health Act 2016 (Qld) (Mental Health Act), which is designed to protect the rights of people with mental illness (for further information see the chapter on Mental Health Laws). The Mental Health Act also correlates with the provisions of the Guardianship and Administration Act 2000 (Qld), which are addressed in the chapter on Laws Relating to Individual Decision Making.

Mental Health Code

The Mental Health Court decides the state of mind of people charged with criminal offences.

The court decides whether an alleged offender was of unsound mind when they committed an offence and whether they are fit for trial.

Fitness to plead and to stand trial

Every accused person is asked to plead guilty or not guilty. Silence is assumed to be a plea of not guilty. A person who is judged to be unfit to plead may still be detained in custody (in jail or a mental health facility) until they are fit to plead.

An accused person must be able to understand the significance of telling the truth to the court, comprehend the nature of the charge and assist with their defence (e.g. able to instruct their solicitor). Someone considered unfit to stand trial can be kept in custody until they are fit to stand trial.

Alternatives to imprisonment

Imprisonment may be an inappropriate sentence for many people with a disability. In the prison environment, a person with a disability may be vulnerable. It is also likely that imprisonment, for many people with a disability, is unlikely to fulfil any of the purposes of punishment such as retribution, rehabilitation, deterrence and community protection.

Even when a person with a disability has been convicted of a serious offence, alternatives to imprisonment exist.

A solicitor who is aware of their client’s disability should attempt to establish whether the client has the ability and willingness to comply with any conditions that might be imposed as part of an alternative punishment. For example, if a person with a disability is placed on a good behaviour bond, they must understand and agree to the ramifications of this before it can be imposed.

Legal representatives should also be aware of the resources and support services available in the community for clients with disabilities (see the Mental Health Laws chapter).