The common law

13.1       Client legal privilege is an ‘important common law immunity’[1] and a ‘fundamental and general principle of the common law’.[2] It ‘exists to serve the public interest in the administration of justice by encouraging full and frank disclosure by clients to their lawyers’.[3]

13.2       This chapter is about client legal privilege—also known as legal professional privilege—as defined by the common law.[4] The chapter discusses the source and rationale for client legal privilege; how the privilege is protected from statutory encroachment; and when laws that abrogate the privilege may be justified.

The doctrine

13.3       The settled doctrine on client legal privilege in Australia is set out in Daniels Corporation International Pty Ltd v Australian Competition and Consumer Commission:

Legal professional privilege is not merely a rule of substantive law. It is an important common law right or, perhaps, more accurately, an important common law immunity. It is now well settled that statutory provisions are not to be construed as abrogating important common law rights, privileges and immunities in the absence of clear words or a necessary implication to that effect.[5]

13.4       The High Court went on to state:

It is now settled that legal professional privilege is a rule of substantive law which may be availed of by a person to resist the giving of information or the production of documents which would reveal communications between a client and his or her lawyer made for the dominant purpose of giving or obtaining legal advice or the provision of legal services, including representation in legal proceedings. It may here be noted that the ‘dominant purpose’ test for legal professional privilege was recently adopted by this Court in Esso Australia Resources Ltd v Federal Commissioner of Taxation in place of the ‘sole purpose’ test which had been applied in Grant v Downs.

Being a rule of substantive law and not merely a rule of evidence, legal professional privilege is not confined to the processes of discovery and inspection and the giving of evidence in judicial proceedings.[6]

13.5       The privilege applies to a range of legal proceedings and can be claimed at ‘interlocutory stages of a civil proceeding, during the course of a civil or criminal trial and in non-judicial proceedings (such as administrative and investigative proceedings or in derogation of a search warrant)’.[7] The onus is on the party asserting the privilege to present the facts that give rise to the claim.

13.6       Litigation and advice privilege are the two main types of client legal privilege, although the distinction between them is sometimes blurred.[8] The test of whether communications or evidence were brought into existence for the dominant purpose of providing legal advice or for use in litigation, is a question of fact.[9] Third party communications may also be protected by client legal privilege where a communication passes between a third party and a lawyer or their client and that communication was made in contemplation of anticipated litigation.[10]

13.7       A claim for client legal privilege will only be successful if the privilege attaches to certain communications between a lawyer and their client. There are a range of communications such as costs agreements that are not protected by client legal privilege:[11]

[O]nly those documents which are brought into existence for the dominant purpose of submission to legal advisers for advice or for use in legal proceedings are entitled to immunity from production.[12]

13.8       Communications may be oral or written as long as the communication is necessary for the purpose of carrying on the proceeding for which the legal practitioner is employed.[13] Further, privilege will only attach to communications made by a lawyer while acting in their professional capacity.[14] Client legal privilege must first be claimed before it has any effect and, given that the privilege is a personal right, must be claimed by the person entitled to it.[15] The privilege covers civil and criminal matters or proceedings.

13.9       There are various rules or exceptions to claims for client legal privilege at common law. For instance, a claim for client legal privilege will fail if the communication that is the subject of the claim was made in furtherance of the following:

  • the commission of a crime;[16]

  • the abuse of a statutory power;[17] or

  • if the claim frustrates a legal process.[18]


13.10   In the ALRC’s 2008 Privilege in Perspective report, a number of rationales were identified for the privilege, including instrumental rationales, so as encouraging full and frank disclosure of evidence and information, encouraging compliance with regulatory bodies, discouraging litigation or encouraging settlement, and promoting the efficient operation of the adversarial system.[19] The ALRC also discussed the importance of safeguarding client legal privilege in order to protect access to justice, facilitating other rights or protections.[20]

13.11   Protecting the confidentiality of communications between lawyers and clients facilitates a relationship of trust and confidence.[21] A confidential relationship encourages clients to communicate in a frank and honest way with their legal representative. Without that confidence, a person may decide—often to their detriment—not to engage a lawyer. The privilege therefore ‘assists and enhances the administration of justice’.[22]

13.12   In Greenough v Gaskell, Lord Brougham explained that the privilege was fashioned ‘out of regard to the interests of justice’,

which cannot go on without the aid of men skilled in jurisprudence, in the practice of the courts, and in the matters affecting rights and obligations which form the subject of all judicial proceedings. If a privilege did not exist at all, everyone would be thrown on his own legal resources. Deprived of all professional assistance, a man would not venture to consult any skilful person, or would only dare to tell his counsellor half of his case.[23]

13.13   In order for lawyers to provide rigorous and targeted legal advice they need to be made aware of all the facts of their client’s case—facts which a client may only feel comfortable disclosing under the protection of confidentiality.[24]

[It is] necessary that a lawyer should be placed in full possession of the facts to enable him to give proper advice and representation to his client, this privilege is granted to ensure that the client can consult his lawyer with freedom and candor; it being thought that if the privilege did not exist a man would not venture to consult any skilled person.[25]

13.14   In Esso Australia Resources v Commissioner of Taxation, Kirby J spoke about the fundamental purpose of the privilege:

It arises out of ‘a substantive general principle of the common law and not a mere rule of evidence’. Its objective is ‘of great importance to the protection and preservation of the rights, dignity and freedom of the ordinary citizen under the law and to the administration of justice and law’. It defends the right to consult a lawyer and to have a completely candid exchange with him or her. It is in this sense alone that the facility is described as ‘a bulwark against tyranny and oppression’ which is ‘not to be sacrificed even to promote the search for justice or truth in the individual case’.[26]


13.15   Client legal privilege has a long history, having existed for over 400 years in English law.[27] Indeed American legal historian, Professor John Wigmore, described the privilege as ‘the oldest of the privileges for confidential communications’.[28]

13.16   The privilege dates from Elizabethan times[29] when it was developed by the courts as a mechanism to underscore the ‘professional obligation of the barrister or attorney to preserve the secrecy of the client’s confidences’.[30] Dr Jonathan Auburn described the privilege as one of the ‘many rules in the large mass of law relating to testimonial compulsion’ that developed in the 16th century.[31]

13.17   Professor John Wigmore explained that the privilege, along with other similar protections in civil and criminal law, developed as a way to invest a sense of sportsmanship into the adversarial justice system:

The right to use a rule of procedure or evidence as one plays a trump card, or draws to three aces, or holds back a good horse til the home stretch is a distinctive result of the common law moral attitude towards parties in litigation.[32]

13.18   The privilege developed significantly in the 18th and 19th centuries in the Chancery courts when it was considered to be only an evidentiary rule.[33] As common law procedures were reformed in the late 19th century, client legal privilege came to be understood as a substantive right. The scope of the common law privilege expanded significantly in the 20th century to take account of new government agencies empowered with coercive information-gathering powers.[34] Indeed the Administrative Review Council noted in 2008 that client legal privilege continues to be an ‘evolving and often contentious area of the law’.[35]

A right?

13.19   The language of ‘rights’ has arisen during the course of the evolution of the privilege at common law.[36] For instance, in Baker v Campbell, Murphy and Deane JJ adopted the terminology of rights when discussing the privilege.[37] This view was endorsed by a majority of the High Court in AFP v Propend Finance.[38]

13.20   Client legal privilege has also been described as a human right, derived from the right to privacy[39] and the right to protection from the state.[40] In Baker v Campbell, Deane J said that it ‘represents some protection of the citizen—particularly the weak, the unintelligent and the ill-informed citizen—against the leviathan of the modern state’.[41]

13.21   Client legal privilege quite clearly interacts with other rights and privileges at common law, including the right to a fair trial[42] and the right to privacy. Murphy J in Baker v Campbell emphasised the protection of a client’s privacy from the intrusion of the state:

The client’s legal privilege is essential for the orderly and dignified conduct of individual affairs in a social atmosphere which is being poisoned by official and unofficial eavesdropping and other invasions of privacy. [43]

13.22   In the same case, Wilson J commented that the ‘adequate protection according to law of the privacy and liberty of the individual is an essential mark of a free society’.[44]