A common law right

12.1       The privilege against self-incrimination is ‘a basic and substantive common law right, and not just a rule of evidence’.[1] It reflects ‘the long-standing antipathy of the common law to compulsory interrogations about criminal conduct’.[2]

12.2       In 1983 the High Court described the privilege as follows:

A person may refuse to answer any question, or to produce any document or thing, if to do so ‘may tend to bring him into the peril and possibility of being convicted as a criminal’.[3]

12.3       Similarly, in 2004 the Full Federal Court said:

The privilege is that a person (not company) is not bound to answer any question or produce any document if the answer or the document would expose, or would have a tendency to expose, the person to conviction for a crime.[4]

12.4       The common law privilege is available not only to persons questioned in criminal proceedings, but to persons suspected of a crime,[5] to persons questioned in civil proceedings[6] and in non-curial contexts.[7]

12.5       The privilege is one aspect of the right to silence.[8] The right to silence protects the right not to be made to testify against oneself (whether or not that testimony is incriminating).[9] The privilege against self-incrimination is narrower, in that it protects the right not to be made to incriminate oneself. A statute might require a person to answer questions, thus breaching the right to silence, but allow the person to refuse to give incriminating answers, thus preserving the privilege against self-incrimination.[10]

12.6       This chapter is only concerned with the privilege against self-incrimination, which arose in the common law courts, rather than the privilege against exposure to a civil penalty or forfeiture, which arose in equity.[11] This is consistent with the Terms of Reference for this Inquiry which require the ALRC to consider laws that encroach on traditional, or common law, rights, freedoms and privileges.

Testimony and documents

12.7       The privilege is testimonial in nature, protecting individuals from convicting themselves out of their ‘own mouths’.[12]

12.8       The privilege does not prevent persons from being compelled to incriminate themselves through the provision of evidence that is non-testimonial in nature.[13] Non-testimonial evidence may include, for instance, fingerprints or DNA samples.[14]In Sorby v Commonwealth, Gibbs CJ explained that the privilege

prohibits the compulsion of the witness to give testimony, but it does not prohibit the giving of evidence, against the will of a witness, as to the condition of his body. For example, the witness may be required to provide a fingerprint, or to show his face or some other part of his body so that he was identified.[15]

12.9       While recent Australian decisions have indicated that the privilege extends to documents,[16] questions have been raised as to whether that continues to be the case. The Australian Securities and Investments Commission (ASIC) noted that in the United States and the United Kingdom, the privilege against self-incrimination no longer extends to the production of documents, but only protects testimonial communications.[17]

12.10   ASIC also noted that doubts have been expressed by Australian courts about the extension of the privilege to documents. In three judgments of the High Court, documents have been referred to as ‘in the nature of real evidence which speak for themselves’, in contrast to testimonial evidence, with the inference that the privilege may be unnecessary with regard to documents.[18] However in those cases it was not necessary for the Court to definitively confirm the existence—or otherwise—of the common law privilege regarding documents.

12.11   If the privilege continues to extend to documents, it only excuses the person from producing them. If the documents are, for example, seized under a warrant, they are not protected by the privilege.[19]

Corporations may not claim the privilege

12.12   The privilege against self-incrimination extends to natural persons, but not corporations.[20] In Environment Protection Authority v Caltex, the High Court reviewed the historical and modern rationales for the privilege and held that these did not support the extension of the privilege to corporations. In particular, the court noted that

a corporation is usually in a stronger position vis-a-vis the state than is an individual; the resources which companies possess and the advantages which they tend to enjoy, many stemming from incorporation, are much greater than those possessed and enjoyed by natural persons … Accordingly, in maintaining a ‘fair’ or ‘correct’ balance between state and corporation, the operation of the privilege should be confined to natural persons.[21]

The origins of the privilege

12.13   There is some debate among legal historians about the origins of the privilege.[22]  Some have suggested it is of ancient origin, arising from the common law maxim nemo tenetur prodere seipsum, meaning that people should not be compelled to betray themselves.[23] Professor Richard Helmholz reports that the ius commune or common law of the 12th and 13th centuries, a combination of the Roman and canon laws, included an early privilege against self-incrimination that influenced the modern iteration of the privilege at common law.[24]

12.14   In his Commentaries on the Laws of England, William Blackstone explained that the maxim was enlivened where a defendant’s ‘fault was not to be wrung out of himself, but rather to be discovered by other means and other men’.[25]

12.15   Others point to the development of the privilege in the 17th century as a response to the unpopularity of the Star Chamber in England whose practices included requiring suspects on trial for treason to answer questions without protection from self-incrimination.[26]

12.16   On the other hand, Professor John Langbein suggested the privilege did not arise until much later. He pointed to the development of the privilege as part of the rise of the adversarial criminal justice system, where the prosecution is charged with proving the guilt of a defendant beyond a reasonable doubt and subject to protections surrounding the manner of criminal discovery.[27]

12.17   In a vigorous dissent in Azzopardi v R,McHugh J endorsed Langbein’s approach:

these lawyers and historians have convincingly demonstrated that the self-incrimination principle originated from the European inquisitorial procedure and that it did not become firmly established as a principle of the criminal law until the mid-19th century or later.[28]

The rationale for the privilege

12.18   A number of rationales have been offered for the privilege. First, and perhaps most importantly, the privilege is said to protect freedom and dignity. In Pyneboard Pty Ltd v Trade Practices Commission, Murphy J explained that the privilege is

part of the common law of human rights. It is based on the desire to protect personal freedom and human dignity. These social values justify the impediment the privilege presents to judicial or other investigation. It protects the innocent as well as the guilty from the indignity and invasion of privacy which occurs in compulsory self-incrimination; it is society’s acceptance of the inviolability of the human personality.[29]

12.19   Also in Pyneboard, the privilege was described as a ‘fundamental bulwark of liberty’.[30]

12.20   Secondly, the privilege is said to be necessary to preserve the presumption of innocence, and to ensure that the burden of proof remains on the prosecution. In Cornwell v The Queen, Kirby J said:

Such self-incrimination has been treated in the jurisprudence as objectionable, not only because the methods used to extract it are commonly unacceptable but because the practice is ordinarily incompatible with the presumption of innocence. This presumption normally obliges proof of criminal wrong-doing from the evidence of others, not from the mouth of the person accused, given otherwise than by his or her own free will.[31]

12.21   Thirdly, the privilege is thought to reduce the power imbalance between the prosecution and a defendant,[32] or as Gleeson CJ put it, to hold ‘a proper balance between the powers of the State and the rights and interests of citizens’.[33]

12.22   In more utilitarian terms, the privilege may offer the following benefits.

  • It may encourage witnesses to cooperate with investigators and prosecutors, as they are able to do so without giving answers to questions that may incriminate them.[34]

  • It may protect individuals from unlawful coercive methods used to obtain confessions.[35]

  • It may reduce the incidence of false confessions. The stressful environment of police interviews may be ‘conducive to false confessions on account of the authority of police, the isolation, uncertainty and anxiety of the suspect and the expectations of the interrogation officer’.[36] Being compelled to give a statement in this environment could exacerbate the problem.

  • It may reduce the incidence of untruthful evidence, on the basis that a person who is compelled to give evidence is more likely to lie.[37]

Statutory protection

12.23   Some statutes protect the privilege against self-incrimination. For example, s 128(1) of the Evidence Act 1995 (Cth) provides that where a witness objects to giving particular evidence that ‘may tend to prove’ that the witness has committed an offence under Australian or foreign law, or is liable to a civil penalty, a court may determine whether there are ‘reasonable grounds’ for an objection to providing that evidence.[38] If there are reasonable grounds, the court is to inform the witness that the witness need not give the evidence.[39]

12.24   In one respect, the Evidence Act offers superior protection than the common law. The Evidence Act requires a court, if it appears that a witness may have grounds to claim the privilege, to ensure that the witness is aware of the privilege.[40] At common law, there is no duty on the judge to warn a witness that there is no obligation to answer incriminating questions,[41] and many judges did not do so before the introduction of the statutory obligation.[42]