Police Interrogation

Contributed by Richard Davies and current to 16 December 2021.

Police powers and responsibilities in relation to the interrogation of suspects is governed by the provisions of the Commonwealth Crimes Act 1914 (''Commonwealth Crimes Act'').

Period of investigation for a non-terrorism offence

A person arrested for an offence may be detained for the purpose of investigating whether the person committed the offence. According to s 23C(4) Commonwealth Crimes Act, a person may be detained for a period not exceeding 4 hours, or in the case of a child or an Aboriginal person or Torres Strait Islander, 2 hours.

Under s 23C(7) Commonwealth Crimes Act, a number of events or circumstances, such as the time taken to convey the person under arrest to a police station or allowing the person to receive medical attention or communicate with a lawyer which result in an interrogation being suspended or delayed are excluded from the calculation of these periods.

Different provisions apply to offences classified as terrorism offences, see relevant s 23DB Commonwealth Crimes Act.

Extension of the investigating period

In the case of a serious offence (punishable by more than 12 months imprisonment and not being a terrorism offence) as per s 23DA Commonwealth Crimes Act, a magistrate may extend the investigation period on the application of an investigating official.

Obligations of investigating police

Cautioning persons

Under s 23F Commonwealth Crimes Act, before a police officer starts questioning a person who is under arrest or detained, the police office must caution the person who is under arrest or detained that he or she does not have to say or do anything, but that anything the person does say or do may be used in evidence.

Right to communicate with friend, relative or lawyer

Before questioning can commence the person under arrest must be informed that he or she may communicate or attempt to communicate with a friend, a relative, and a lawyer of the person’s choice or attempt to arrange for a lawyer of the person’s choice to be present during questioning. Questioning must be deferred for a reasonable time to allow these to occur, see s 23G(1) Commonwealth Crimes Act.

A person under arrest who wishes to communicate with a friend, relative or lawyer must be provided reasonable facilities (a telephone, and maybe a chair) and in the case of communicating with a lawyer, a private place where the communication will not be overheard, see s 23G(2) Commonwealth Crimes Act.

If a lawyer attends, the person under arrest must be allowed to consult with the lawyer in private and in reasonable facilities and the lawyer must be allowed to be present during the questioning and to give advice to the person, see s 23G(3) Commonwealth Crimes Act.

Obligations in relation to Aboriginal and Torres Strait Islanders

According to s 23H(1) Commonwealth Crimes Act, if police believe on reasonable grounds that the person who is under arrest and whom it is intended to question about the offence is an Aboriginal person or Torres Strait Islander, the police officer must immediately inform the person that a representative of the Aboriginal Legal Service will be notified that the person is under arrest and then notify the organisation.

The Aboriginal Legal Service (NSW/ACT) Limited operates a custody notification service for New South Wales and the ACT. The Custody Notification Service (CNS) is a 24-hour legal advice phone line for Aboriginal people taken into police custody. Police phone the CNS, and the Aboriginal person receives early legal advice from an ALS lawyer, ensuring their fundamental legal rights are respected. The CNS lawyers can also contact the person’s family and an Aboriginal Field Officer, ensuring parental or family concern for that person’s whereabouts and health are minimised.

In addition, an Aboriginal person or Torres Strait Islander may not be questioned unless an interview friend is present while the person is being questioned.

The person may choose their own interview friend (for example, a relative, a friend, a representative from the Aboriginal Legal Service such as a field officer or a lawyer), see s 23H(9) Commonwealth Crimes Act.

If the person fails to choose their own interview friend, the police officer must choose one from a list of interview friends kept by police for that purpose or a representative of the Aboriginal Legal Service, see s 23H(2) Commonwealth Crimes Act.

However the person under arrest may voluntarily choose to waive the right to an interview friend, see relevant section 23H(2)(d) Commonwealth Crimes Act.

An interview friend may be excluded from the questioning if he or she unreasonably interferes with it, see relevant section 23H(3) Commonwealth Crimes Act.

Obligations in relation to persons under 18 years of age

Under s 23K(1) Commonwealth Crimes Act, a person who is a suspect for an offence (whether or not under arrest) believed by police to be under the age of 18 years must not be questioned by police unless an interview friend is present. Before the questioning commences the police officer must allow the person to communicate with the interview friend in private.

For this purpose an interview friend may be a parent, a guardian or a lawyer; if none of these are available a relative or friend who is acceptable to the person; if none of these are available then an independent person, or if the person is an Aboriginal or Torres strait Islander, someone on the list of interview friends kept by police for that purpose or a representative of the Aboriginal Legal Service, see s 23K(3) Commonwealth Crimes Act.

Providing information relating to detained persons to third parties

If a friend or a relative of a person under arrest, or the person’s lawyer requests information as to his or her whereabouts from a police officer, that officer must inform the person under arrest of that request and provide the information requested unless the person under arrest does not agree, or the police officer does not believe on reasonable grounds that the other person is a relative or friend or the lawyer of the person under arrest, see s 23M Commonwealth Crimes Act.

Right to an interpreter

If a police officer believes that a person under arrest is unable to communicate fluently because of inadequate knowledge of the English language or a physical disability the police officer must arrange for the presence of an interpreter before questioning commences, see s 23N Commonwealth Crimes Act.

A telephone interpreter may be sufficient for this purpose.

Right of non-Australian nationals to communicate with consular office

Under s 23P Commonwealth Crimes Act, if a person under arrest is not an Australian citizen a police officer must as soon as practicable inform the person of his or her right to have the police officer notify the consular office of the country of which he or she is a citizen or to which he or she claims a special connection.

If the person requests that their consular office be notified, the police officer must:

• notify the consular office;
• inform the person that he or she may communicate with the consular office;
• provide reasonable facilities to do so;
• forward any written communication from the person to the consular office; and
• allow the person a reasonable time to communicate or attempt to communicate with the consular office.

Treatment of persons under arrest

A person who is under arrest must be treated with humanity and with respect for human dignity, and must not be subjected to cruel, inhuman or degrading treatment, see s 23Q Commonwealth Crimes Act and s 19 Human Rights Act 2004 (ACT).

Right to remain silent

The caution referred to in Cautioning Persons above, see s 23F Commonwealth Crimes Act, reflects a fundamental principle of the common law, that the citizen has the right to remain silent when questioned by police as a suspect in relation to a criminal investigation.

It follows upon the right to silence that no adverse inference can be drawn against an accused person by reason of his or her failure to answer questions or to provide information to investigating police.

It also follows from the right to silence that an accused person is to be presumed innocent and consequently as a general rule an accused person does not have to prove their innocence or anything else at their trial, but rather the prosecution must prove their guilt, and prove it beyond reasonable doubt.