9.9 While the Australian Constitution does not expressly protect the presumption of innocence, academic and juridical discussion has suggested that the presumption may be considered part of the broader concept of a fair trial entrenched in common law.
9.10 In Carr v Western Australia (2007), Kirby J spoke about an ‘important feature of the Australian criminal justice system’:
Trials of serious crimes, such as the present, are accusatorial in character. Valid legislation apart, it is usually essential to the proper conduct of a criminal trial that the prosecution prove the guilt of the accused and do so by admissible evidence. Ordinarily … the accused does not need to prove his or her innocence.
9.11 Kirby J said that this feature of the criminal justice system is ‘not always understood’, yet
it is deeply embedded in the procedures of criminal justice in Australia, inherited from England. It may even be implied in the assumption about fair trial in the federal Constitution.
9.12 In separate judgments in Dietrich v The Queen (1992),Deane and Gaudron JJ also relied on Chapter III of the Australian Constitution, which establishes the judicial branch of government, as authority for the protection of a fair trial.
Principle of legality
9.13 The principle of legality provides some protection for the principle that the prosecution should bear the burden of proof in criminal proceedings. When interpreting a statute, courts will presume that Parliament did not intend to reverse or shift the burden of proof, unless this intention was made unambiguously clear. In Momcilovic v The Queen (2011), French CJ held that
The common law ‘presumption of innocence’ in criminal proceedings is an important incident of the liberty of the subject. The principle of legality will afford it such protection, in the interpretation of statutes which may affect it, as the language of the statute will allow. A statute, which on one construction would encroach upon the presumption of innocence, is to be construed, if an alternative construction be available, so as to avoid or mitigate that encroachment. On that basis, a statute which could be construed as imposing either a legal burden or an evidential burden upon an accused person in criminal proceedings will ordinarily be construed as imposing the evidential burden.
9.14 The question in Momcilovic was whether s 5 of the Drugs, Poisons and Controlled Substances Act 1981 (Vic)imposed a legal or evidentiary burden on a defendant to prove on the balance of probabilities that they had no knowledge of the presence of drugs in their possession:
The principle of legality at common law would require that a statutory provision affecting the presumption of innocence be construed, so far as the language of the provision allows, to minimise or avoid the displacement of the presumption. But, for the reasons which follow, its application to s 5 cannot yield a construction other than that required by the clear language of that section, which places the legal burden of proof on the accused.
9.15 The ICCPR protects the presumption of innocence:
Everyone charged with a criminal offence shall have the right to be presumed innocent until proved guilty according to law.
9.16 International instruments cannot be used to ‘override clear and valid provisions of Australian national law’. However, where a statute is ambiguous, courts will generally favour a construction that accords with Australia’s international obligations.
Bills of rights
9.17 In other countries, bills of rights or human rights statutes provide some protection to certain rights and freedoms. The Fourteenth Amendment to the US Constitution guarantees a right not to be deprived of ‘life, liberty or property’ and has been interpreted by the US Supreme Court as including a presumption of innocence. The Canadian Charter of Rights and Freedoms provides that any person charged with an offence has the right to be presumed innocent until proven guilty.
9.18 The European Convention for the Protection of Human Rights and Freedoms provides
Everyone charged with a criminal offence shall be presumed to be innocent until proved guilty according to law.
9.19 The Victorian Charter of Human Rights protects the presumption that the legal onus of proving the facts of a case rests on the party asserting a wrong. As does the ACT’s Human Rights Act (2004).
Carr v Western Australia (2007) 232 CLR 138, 172 (Kirby J in dissent, obiter). See further, Anthony Gray, ‘Constitutionally Protecting the Presumption of Innocence’ (2012) 31 University of Tasmania Law Review 132; Dietrich v The Queen (1992) 177 CLR 292, 326 (Deane J) and 362 (Gaudron J); Fiona Wheeler, ‘The Doctrine of Separation of Powers and Constitutionally Entrenched Due Process in Australia’ (1997) 23 Monash University Law Review 248, 248.
Dietrich v The Queen (1992) 177 CLR 292, 326 (Deane J) and 362 (Guadron J). See also, Nicholas v The Queen (1998) 193 CLR 173, 208–209 (Gaudron J). On fair trials more generally, see Ch 8.
The principle of statutory interpretation now known as the ‘principle of legality’ is discussed more generally in Ch 1.
Momcilovic v The Queen (2011) 245 CLR 1.
Ibid  (French CJ).
Ibid  (Crennan & Kiefel JJ).
International Covenant on Civil and Political Rights, opened for signature 16 December 1966, 999 UNTS 171 (entered into force 23 March 1976) art 14(2).
Minister for Immigration v B (2004) 219 CLR 365, 425  (Kirby J).
Minister for Immigration and Ethnic Affairs v Teoh (1995) 183 CLR 273, 287 (Mason CJ and Deane J). The relevance of international law is discussed more generally in Ch 1.
United States Constitution amend IV.
Re Winship  397 US 358 (1970).
Canada Act 1982 c 11, Sch B Pt 1 (’Canadian Charter of Rights and Freedoms’) s 11(d). The protection provided by bills of rights and human rights statutes is discussed more generally in Ch 1.
European Convention for the Protection of Human Rights and Fundamental Freedoms, opened for signature 4 November 1950, 213 UNTS 221 (entered into force 3 September 1953) art 6(2).
Charter of Human Rights and Responsibilities Act 2006 (Vic) s 25(1).
Human Rights Act 2004 (ACT) s 22(1).