The privilege against self-incrimination is a long-established principle of the criminal law, recognized in both statute and common law. Provision is made for it in each Australian jurisdiction's Evidence Act. The High Court of Australia has even attributed the status of a human right to the privilege: Environment Protection Authority (NSW) v Caltex Refining Co Pty Ltd (1993) 178 CLR 477; 68 ALJR 127; 82 LGERA 51 .

The case of Environment Protection Authority (NSW) v Caltex Refining Co Pty Ltd is also interesting for the light it sheds on the intersection of human rights discourse with arguments in favour of the adversarial system of justice. It has been argued that the different weights attached by the High Court justices to different explanations of the privilege influenced their views on whether corporations were entitled to the privilege against self-incrimination. The majority position focused on a human rights argument for the protection of individual dignity and privacy and the maintenance of a balance between the State and the individual. The minority judgment took the view that the privilege emanates from, reflects, and supports the adversarial system of justice in which the prosecution is required to prove the guilt of an accused person.

Dealing with this latter position first, the champions of the adversarial system argued that the privilege against self-incrimination should be accorded to corporations as an incident of the onus of proof resting on the prosecution:

The privilege against self-incrimination confers an immunity which is deeply embedded in the law. In the end, it is based upon the deep-seated belief that those who allege the commission of a crime should prove it themselves and should not be able to compel the accused to provide proof against himself. To make an exception in the case of a corporation may trouble the conscience less because a corporation ‘has no body to be kicked or soul to be damned’. But that is hardly a sufficient justification for the exception having regard to the underlying principle and the purpose which it serves, both of which apply to corporations.

For those justices in the majority who took the human rights line, the principle against self-incrimination was available only to individuals and not to corporations. As Mason CJ and Toohey J in the majority put it:

The privilege in its modern form is in the nature of a human right, designed to protect individuals from oppressive methods of obtaining evidence of their guilt for use against them. In respect of natural persons, a fair state-individual balance requires such protection [the privilege]; however, in respect of corporations, the privilege is not required to maintain an appropriate state-individual balance.

With its acknowledgement that corporations are much better placed than individuals to defend themselves in relation to the prosecutorial functions of the State, this argument for denying the availability of the privilege to corporations betrayed recognition of the actual disparities in power and resources between those at the receiving end of criminal justice. This recognition of actually existing inequality seems somewhat paradoxical within an argument founded on the liberal understanding of human rights – with its premise of the universal, individual, intrinsic, formal, equality of all humans.

It begs the question: What place should considerations of the reality of substantive social inequalities have in informing the application of human rights principles in the law?

The privilege against self-incrimination is discussed in updated The Laws of Australia Subtitle 21.6 “Justice”.

For more information about The Laws of Australia, click here.