544. The General Law. Before considering the special problems which arise in the investigation and interrogation of Aboriginal suspects, it is necessary to describe briefly the general law regulating police questioning of suspects and the right to silence. Three basic statements can be made. First, police have the right to question any person at any time when investigating a crime. Second, a person cannot be compelled to answer such questions: a suspect has the right to remain silent and no adverse inference may be drawn from the exercise of this right. Third, two distinct rules apply to the admissibility in evidence of any confession or admission made to the police: (1) to be admissible the statement must be voluntary and not the result of ‘duress, intimidation, persistent importunity, or sustained or undue insistence or pressure’; (2) even if a statement is found to be voluntary it may still be excluded in the exercise of the judge’s discretion if it is considered that it would be unfair to the accused to receive it in evidence. A relevant factor in determining unfairness is whether the Judges Rules have been adhered to by the police when questioning the accused person, although non-compliance with the Judges Rules does not result in automatic exclusion of the evidence obtained. These principles have been restated by Chief Justice Gibbs:
The principles governing the admissibility of confessional evidence are not in doubt … A confession will not be admitted unless it was made voluntarily, that is in the exercise of a free choice to speak or be silent. But even if the statement was voluntary, and therefore admissible, the trial judge has a discretion to reject it if he considers that it was obtained in circumstances that would render it unfair to use it against the accused.
545. The Judges Rules. In 1912 the Judges of the Kings Bench in England laid down a set of guidelines for the police when questioning suspects. Various amendments have been made to the rules since that time and a complete revision was published in 1964. Versions of the Judges Rules in their pre-1964 form apply in most Australian jurisdictions either by incorporation in police standing orders or by adoption by the relevant court as guidelines in exercising its discretion to exclude confessions. The Judges Rules attempt to balance the competing principles of the protection of the rights and liberties of the individual citizen and the interest of the community in bringing offenders to justice, which requires that the police be granted sufficient powers to investigate crime. Their principal requirement is that a person who is to be subjected to police questioning by the police be told of his right to remain silent: this is to be done by the police issuing a caution to this effect at various stages of the investigation. Other rules regulate the extent to which questions may be asked, especially where a person is making a voluntary statement. The rationale for the rules was well expressed by the Royal Commission on Criminal Procedure (UK) in 1981:
The presumption behind the Judges Rules is that the circumstances of police questioning are of their very nature coercive, that this can affect the freedom of choice and judgement of the suspect (and his ability to exercise his right of silence), and that in consequence the reliability (the truth) of statements made in custody has to be most rigorously tested.