While Australia’s legal system, including the common law, is not bound by international law, international law can play a significant role in the interpretation and evolution of the common law system. In the landmark decision of Mabo, Justice Brennan notes that ‘the common law does not necessarily conform with international law, but international law is a legitimate and important influence on the development of the common law’. This essay will examine the role of international law in the development of the common law. In particular, the independence of the common law will be examined through the cases of Western Australia v Ward and Dietrich v The Queen. It will be shown that while the common law is indeed independent, international law can be used to interpret any ambiguities. The cases of Mabo and Teoh will be used to further show that international law can be used to reinterpret the common law when the common law is indeed out of line with international law. The continued use of international law will hopefully guide the Australian system to be more in line with the international community, especially in regards to international human rights standards.
II The Australian Legal System
A Common Law
Australia inherited the common law system from the English law system on the 26 January 1788, in accordance with William Blackstone’s Commentaries. The common law is a system of unwritten law that is based on precedence from previous judgements, in which the lower courts are bound to follow the precedence of higher courts if the cases are simular. As the common law is bound by previous judgements, the common law can often be more conservative in its approach to the evolution of legal principles. Thus, even as perceptions of the general public change, it can take a while for the common law system to adapt to new values of the community. As such, many, such as Justice Brennan, have argued that the common law should be more heavily interpreted or expanded in accordance with contemporary values. Hence, many have called for greater use of international in the development of the common law system in order to progress the common law further in line with the international community, especially in cases of human rights law.
1 Influence of Other Jurisdictions on the Common Law System
Indeed, Australia’s common law system is already influenced by a number of different jurisdictions. Firstly, within the state system, decisions by courts in other states are considered persuasive, with higher courts being highly persuasive. However, Australian common law can also be influenced by decisions in other countries, especially other common law countries. Australian courts continually refer to decisions made by courts in Canada, England and the United States. As such, there are those who argue that international law should be no different. Shane Monks argues that references to international materials require no great leap in the established judicial method observed in common law countries:
Australian courts have always made reference to case law from other common law jurisdictions…There is no logical reason why international law should be a less acceptable source of comparative law than any other municipal jurisdiction. On the contrary, its acceptance by many different jurisdictions should make it a more acceptable source of comparison.
As such, there is a significant role of international law on the development of the common law system.
B International Law
International law can be defined as the ‘body of law which participating nations recognise as binding them in their conduct towards each other’. However, international law, in particular human rights law, has also increasingly been concerned with a nation state’s interaction between it’s own public. International law, and especially public international law, plays a significant role in the development of the Australian legal system. International law includes two distinct sources of law: customary international law and international conventions and treaties. Customary international law is a legal system that is based upon continued customs of nation states, in which general state practice has become the rule of law. These customary international laws are continually argued and challenged, and as such can be sometimes hard to define. On the other hand, international treaties and conventions are much clearer in their purpose and legal principles, and are signed and ratified by participating nation states. The Honourable Michael Kirby has found that there has ‘been the absence of a sharp distinction in the Australian cases between customary international law and treaty law. In general, Australian courts have not sought to apply different rules to international law, according to its origins.’
Australia’s legal system does not automatically incorporate international law into domestic law, and international treaties first have to go through the domestic system of the legislature before they are applicable on a domestic level. As Mason CJ and Deane J point out in Teoh:‘it is well established that the provisions of an international treaty to which Australia is a party do not form part of Australian law unless those provisions have been validly incorporated into our municipal law by statute’.
As Australia does not have it’s own bill of rights or human rights act, many have pointed to the importance of international human rights law in order to develop Australia’s legal system in accordance with human rights standards. Thus it has been argued that international law should play a larger role in the interpretation of the Australian legal system, including the common law. However, as it will be shown, there are still many obstacles in the adoption of international law in the development of the common law system.
III The Independence of the Common Law
As Justice F.G. Brennan notes in Mabo v Queensland (No 2), ‘the common law does not necessarily conform with international law’. The common law, by definition, is independent of other sources of law, and as such is not bound by international law. In fact, the High Court has been hesitant to incorporate other legal principles into the common law system. Commentators have pointed to a fear in the Australia legal system to use international law as a tool in developing the common law:
[T]here is a fear that international law undermines Australian sovereignty or the capacity to govern ourselves as we choose. Anxiety is also fuelled by a perception (akin to a form of legal xenophobia) that international law is an intrusion from ‘outside’ into our self- contained and carefully bounded legal system.
As such, the common law is often seen an independent source of law that should not be undermined by outside influences. Indeed, the entire system of the common law is based on the idea of the fairness of treating simular facts with the same outcome. There is a fear that if outside forces change the common law system, the fairness of precedence will no longer apply. As precedence is the central aspect of the common law, many see international law as a threat to the entire common law system. This fear if often reinforced by decisions of the High Court in its hesitance to apply international law in order to change the common law. Often the High Court has chosen to continue the common law interpretation even if it is inconsistent with international law, as can clearly be shown in the following two cases.
A Western Australia v Ward
In the case of Western Australia v Ward the High Court was asked to consider if partial extinguishment of Aboriginal land rights existed. The Human Rights and Equal Opportunity Commission made a submission to the High Court concerning the relevance of international law to the development of the common law. The Human Rights and Equal Opportunity Commission argued ‘that common law was obliged to develop in accordance with international law’, such as the International Covenant on Civil and Political Rights (ICCPR). However, Justice Callinan rejected the submission, responding:
There is no requirement for the common law to develop in accordance with international law. While international law may occasionally, perhaps very occasionally, assist in determining the content of the common law, that is the limit of its use.
In arguing his position, Callinan J stated:
The proposition that international law…demands that the common law of Australia be moulded in a particular way, apparently without regard for precedent, the conditions in this country, or the fact that governments and individuals may have reasonably relied on the law as it stands is unacceptable.
Justice Callinan’s view echoes the fear that Charlesworth et al refer to. It is clear to see that there are those within the High Court who oppose the influence of international law. The common law, especially the concept of precedence, is often upheld as something that should not be changed or interfered with, and thus calls to use international law in the development of the common law are seen as a threat. This hesitation to use international law to change the common law is also reflected in the case of Dietrich v The Queen.
B Dietrich v The Queen
In Dietrich v The Queen, the applicant sought recognition from the High Court of a common law right to legal representation at public expense, in accordance with the ICCPR. The ICCPR states in art 14(3)(d) that everyone shall be entitled ‘to have legal assistance assigned to [them], in any case where the interests of justice so require, and without payment by [them] in any such case if [they do] not have sufficient means to pay for it’. As pointed out above, international treaties such as the ICCPR do not automatically form part of the Australian legal system, and thus while Australia is a signatory to the ICCPR, it has not yet been implemented into domestic law, and thus the convention is not directly applicable to domestic law. In addition, Brennan J found that the common law had not previously recognized the right to counsel at public expense.As such, the court was asked to declare the existence of a right that had not previously been recognised under common law, thus creating new law. The question before the court was if the common law should be extended to be in line with the ICCPR. The members of the High Court unanimously decided not to change the common law by reference to international law to incorporate an absolute right to counsel. However, as Fitzgerald affirms, the influence of the ICCPR was clearly a key part of the decision that the plaintiff did not receive a fair trial.
Thus the case of Dietrich v The Queen shows that the international law can be used to influence the decision of the common law, even if it does not change the common law. The High Court stated that they would not extend or modify the common law in order for it to be compatible with international law. However, Dietrich also contained a significant discussion about the use of international law in interpreting ambiguity in the common law. The court pointed out that international law could be used to interpret the common law if the common law was unclear. While this did not effect the decision of the court, as the common law was deemed to be clear, it does show a significant use of international law. As Charlesworth et al summarise:
Toohey thought that customary international law could be used to address lacunae in the common law, as well as ambiguities. Brennan J held that the common law could be expanded or even modified to correspond to contemporary values reflected in customary international law, however, he recognised limits based on separation of powers and policy grounds. Mason CJ, McHugh J and Dawson J expressed the narrowest approach, finding that customary international law could only be used to address ambiguities or uncertainties in the common law.
Thus, while the common law may not be altered to conform to international law, international law does play an important role in interpreting the common law.
IV The Use of International Law in Interpreting The Common Law
While it has been shown that the common law is independent of international law, international law does play a significant role in interpretation of common law principles, especially when there is an ambiguity of law. Many of the Judges of the high court have held the view that international law plays an important role in the interpretation of the common law. Chief Justice Mason and Justice Toohey, jointly stated in the case of Environment Protection Authority v Caltex Refining Co Pty Ltd that:
[I]nternational law, while having no force as such in Australian municipal law, nevertheless provides an important influence on the development of Australian common law, particularly in relation to human rights.
However, Justice Brennan favours a stronger use of international law in the development of the common law, as seen in the cases of Dietrich v The Queen and in Mabo. In Dietrich, Brennan J states that the ICCPR is a ‘legitimate influence on the development of the common law’, arguing that the courts have a capacity to expand the common law to correspond to international human rights standards, especially when the common law is inconsistent with international law. This can be seen in Mabo where Brennan J argues for a re-evaluation of common law principles in order to conform to international standards.
A Mabo v Queensland (No 2)
The case of Mabo v Queensland (No 2) revolved around the issues of native title and terra nullius. The court was asked to find if the Meriam people were entitled to ownership of land on the Murray Islands. The court found in favour of the plaintiffs agreeing that concept of native title existed in the common law system, after re-evaluating the common law in light of international law. International law was influential in deciding the outcome of the case, as Brennan J argues:
A common law doctrine founded on unjust discrimination in the enjoyment of civil and political rights demands reconsideration. It is contrary both to international standards and to the fundamental values of our common law to entrench a discriminatory rule which, because of the supposed position on the scale of social organization of the indigenous inhabitants of a settled colony, denies them a right to occupy their traditional lands.
Thus international law, such as the ICCPR, can be used to reinterpret the common law when the court finds that the previous assumption is inconsistent with international law. Furthermore, such as in the case of Teoh, international treaties and conventions that have been ratified by Australia can provide the High Court with expectations that the government would adhere to such treaties in administrative procedures.
B Minister of State for Immigration and Ethnic Affairs v Teoh.
The case of Teoh involveda Malaysian citizen on a temporary visa who was to be sent back to Malaysia because a previous criminal record meant he failed the good character test required for residency. The High Court found that the immigration minister did not take the rights of Ah Teoh’s child, who was an Australian citizen, into consideration when deciding it’s outcome, in accordance with the Convention of the Right of the Child (CRC). Australia is a signatory to the CRC, although the convention has not been implemented into domestic legislation.
The ‘High Court held that the ratification of a treaty by the executive could give rise to a legitimate expectation that a Minister and administrative decision-makers would comply with the obligations imposed by that treaty.’ Thus, even though Australia had not implemented the CRC into domestic law, the act of ratification can provide an expectation that the Australian government would adhere to the convention, providing the chance for judicial review of executive action. Therefore it was found that the Minister for Immigration should have provided Teoh the chance present a submission on how the decision would have affected his child.
However, after the decision of Teoh the Government sought to enact the Administrative Decisions (Effect of International Instruments) bill into parliament, in order to reverse the affect that Teoh had on Australian administrative law. While this bill was never passed through parliament, it shows that there is still a great hesitation in incorporating international law into the Australian legal system.
C International Law and the Separation of Powers
While international law can play in important role in the development of the common law, international law itself cannot be used to change the law all together. Justice Brennan, in Dietrich, pointed to the limitation of the High Court to change the law, because of the separation of powers between the legislature, the executive and the judicial systems:
Although the courts have a broad charter, there are limits imposed by the constitutional distribution of powers among the three branches of government and there are limits imposed by the authority of precedent not only on courts bound by the decisions of courts above them in the hierarchy but also on the superior courts which are bound to maintain the authority and predictability of the common law. Most significantly, there are limits inherent in the very technique by which the courts develop the common law.
This is reflected in Brennan’s previous statement in Mabo that the courts would not alter the law:
In discharging its duty to declare the common law of Australia, this Court is not free to adopt rules that accord with contemporary notions of justice and human rights if their adoption would fracture the skeleton of principle which gives the body of our law its shape and internal consistency.
While the common law should be interpreted to reflect international law standards, it cannot be altered altogether simply by the High Court. For complete transformation of the common law, the law needs to be passed through legislature. However, the use of international law in the development of the common law is a positive step in ensuring that Australia is consistent with the international community and international human rights standards.
V The Appropriate Role of International Law
International law should play a greater role in the development of the common law because it ensures the Australian system is continually evolving to be more in line with the international community. This is especially important when considering that Australia is yet to implement a human rights act. A key part of the common law is its ability to reflect contemporary values of the community. As the world continues to become more globalised, international law is having a greater influence on the values of the Australian community. As The Honourable Michael Kirby affirms,
Technology, including media, affords today’s judges and litigants a much wider context for the expression of values simply because this is the world that the judges and litigants inhabit for which the municipal common law must now be expressed…litigants and the wider community generally expect a country’s laws, including the common law, to be in broad harmony with any relevant provisions of international law…it derives from the reality of life in what is now a closely interconnected world.’
As noted above, international law cannot bring about new laws by itself, however, it can aid the evolution of the common law though the continual use of interpretation and expansion. Indeed, this use of international law is consistent with the Bangalore Principles, as advanced by Kirby:
Bangalore Principle sought to encourage the use of international law as one source of legal principles that, by a process of judicial reasoning from context and by analogy, could guide the development of the local common law where ambiguity or uncertainty arose as to the content of that law.
However, international law should not only be used to interpret ambiguities in the common law. Indeed Chief Justice Mason and Justice Deane argue for a broad interpretation of ambiguity to allow for international law to be used when the common law is inconsistent with international law:
[T]here are strong reasons for rejecting a narrow conception of ambiguity. If the language of legislation is susceptible of a construction which is consistent with the terms of the international instrument and the obligations which it imposes on Australia, then that construction should prevail.
Thus, international law should be used whenever an interpretation consistent with international law will allow, thus providing a broader use of international law. Indeed, even if there is no ambiguity in the common law, when the common law is found to be contrary to international law, ‘it is permissible and proper for an Australian court to re-examine the Australian common law, as the High Court did in Mabo.’ By allowing international law to be used more widely, international law can have a greater impact on the development of the common law, and indeed the entire Australian legal system.
Thus, there are two options before the courts in the use of international law to develop the common law. Firstly, the court can seek to use international law to fill a gap in the common law when an ambiguity exists. Secondly, if the court finds the common law is inconsistent with Australia’s international law obligations, it can seek to reinterpret the common law to be in line with international law.
However, the use of international law in the development of the common law should not become the only use of international law in Australia’s legal system. The intention of ratifying international conventions and treaties is to implement them into legislation, not just to use them as common law interpretation tools.
To conclude, international law, and in particular human rights law, plays a significant role in the development of the common law. The cases examined show that while there is some hesitance to use international law in the Australian legal system, international law is becoming increasingly accepted. In particular, international law plays a significant role in interpreting the common law when there is an ambiguity in the common law. Furthermore, international law can be used to reinterpret the common law when the common law is clearly out of line with international standards. As such, the continued use of international law will hopefully guide the Australian system to be more in line with the international community. However, international law should not just be used in interpreting common law ambiguities, but should be implemented fully into domestic legislation as originally intended by the treaties.
 Mabo v Queensland (No 2) (1992) 175 CLR 42.
 William Blackstone, Commentaries on the laws of England (Burn and Williams, 11th ed, 1791) vol 1, 108; Catriona Cook et al, Laying Down the Law (LexisNexis Butterworths, 8th ed, 2011) 38-9.
 Dietrich v R (1992) 177 CLR 319.
 Shane S Monks, ‘In Defence of the Use of Public International Law by Australian Courts’ (2002) 22 Australian Year Book of International Law 222.
 Peter Butt, Butterworths concise Australian legal dictionary (LexisNexis Butterworths, 3rd ed, 2004).
 Cook et al, above n 2, 52.
 Michael Kirby, ‘International Law and the Common Law: Conceptualising the New Relationship’ (Speech delivered at the Fourth James Crawford Biennial Lecture on International Law, The University of Adelaide, 14 October 2009), 26 <http://www.michaelkirby.com.au/images/stories/speeches/2000s/2009+/2424C.James_Crawford_Lecture_Oct_2009.pdf>.
 Minister of State for Immigration & Ethnic Affairs v Ah Hin Teoh (1995) 183 CLR 286–7.
 Mary Crock and Daniel Ghezelbash, ‘Due process and rule of law as human rights: The High Court and the “offshore” processing of asylum seekers’ (2011) 18 Australian Journal of Administrative Law 101.
 Mabo v Queensland (No 2) (1992) 175 CLR 42.
 Hilary Charlesworth et al, ‘Deep anxieties: Australia and the international legal order’ (2003) 25 Sydney Law Review 424.
 Western Australia v Ward (2002) 213 CLR 1.
 Bret Walker and Sarah Pritchard, Outline of submissions of the Human Rights and Equal Opportunity Commission intervening before the High Court in Miriuwung Case 7 January 2002 <http://www.hreoc.gov.au/legal/submissions_court/guidelines/submission_miriuwung.html>.
 Western Australia v Ward (2002) 213 CLR 389.
 Dietrich v R (1992) 177 CLR 292
 Hilary Charlesworth et al, above n 11, 453.
 International Covenant on Civil and Political Rights, opened for signature 19 December 1966, 999 UNTS 171 (entered into force 23 March 1976).
 Hilary Charlesworth et al, above n 11, 453.
 Dietrich v R (1992) 177 CLR 318–319.
 Charlesworth et al, above n 11, 454.
 Ibid 455.
 Brian F. Fitzgerald, ‘International human rights and the High Court of Australia’ (1994) 1 James Cook James Cook University Law Review 87–8.
 Charlesworth et al, above n 11, 455.
 Environment Protection Authority v Caltex Refining Co Pty Ltd (1993) 178 CLR 499.
 Dietrich v R (1992) 177 CLR 321.
 Mabo v Queensland (No 2) (1992) 175 CLR 1.
 Ibid 42.
 Minister of State for Immigration & Ethnic Affairs v Ah Hin Teoh (1995) 183 CLR 273.
 Convention on the Rights of the Child, opened for signature 20 November 1989, 1577 UNTS 3 (entered into force 2 September 1990).
 Michael Kirby, above n 7, 33.
 Administrative Decisions (Effect of International Instruments) Bill 1997 (Cth)
 Dietrich v R (1992) 177 CLR 320.
 Mabo v Queensland (No 2) (1992) 175 CLR 29.
 Michael Kirby, above n 7, 42–44.
 Ibid 29.
 Minister of State for Immigration & Ethnic Affairs v Ah Hin Teoh (1995) 183 CLR 287.
 Michael Kirby, ‘The Growing Impact of International Law on Australian Constitutional Values’ (Speech delivered at the Australian Red Cross National Oration, TheUniversity Of Tasmania, 8 May 2008), 14 <www.hcourt.gov.au/assets/publications/speeches/former-justices/kirbyj/kirbyj_8may08.pdf>.