While there was a decrease in use of American cases in Constitutional law matters during the period when Dixon was Chief Justice, there was an increase in citation of American cases in tort matters. He had probably become more familiar with American authorities following his sojourn in America in the 1940s. But a brief examination of a number of High Court tort matters reveals that he tended to cite American cases for the purpose of comparing or contrasting factual circumstances, and for contrasting the English and American law, rather than for seeking assistance in finding an answer to a legal problem. Often, the American cases were criticised for adopting a policy or "rationalisation" approach to the law rather than taking the legalistic approach of the Australian High Court and English courts.

In Bryan v. Maloney, Mason CJ, Deane and Gaudron JJ looked at policy considerations in developing the law relating to the tort of negligence, citing with approval Cardozo CJ of the New York Supreme Court, and Wright and Thayer JJ of the Supreme Court of New Hampshire, and referring to judgments of the Supreme Courts in a variety of other United States jurisdictions. This liberal citation of American cases used in support of developments in Australian law concerning negligence can be contrasted with Mason J's approach some 16 years earlier in SGIC v. Trigwell, in which he rejected an argument that the Court should re-examine the appropriateness of certain English case law concerning negligence given modern Australian circumstances, saying, "The Court is neither a legislature nor a law reform agency." No American cases were cited by any of the judges in Trigwell's Case, where the court clearly felt constrained to follow the common law of England. But in 1995, Mason CJ cited American cases from different State jurisdictions for assistance in developing the law of negligence for Australian purposes. In commenting on this change in approach by Mason during his period as a High Court Judge, Kirby J said:

Kirby J ascribed this change in attitude in Mason not merely to facts personal to Sir Anthony such the indirect effect of Murphy J through his influence on other judges with whom Mason felt an affinity, especially Deane J, but also a new national vision symbolised by the High Court's move to Canberra, and the growth of Australia to nationhood and independence through the passage of the Australia Acts, the changed role of the High Court by the introduction of special leave, the decline and fall of the declaratory theory of judicial function, disillusionment with Parliament, outreach to the public through attendance at conferences, and international links.

These are all factors that would have encouraged recourse to American cases as a new source of inspiration for the development of a peculiarly Australian common law.

The increase in the citation of American cases in the last decade is most striking in the area of criminal law. There was virtually no use of American cases in this area until the 1980s.

Two cases stand out in the High Court's use of American case law. Dietrich's Case concerned the right to legal representation in criminal trials, and Ridgeway's Case concerned the exclusion of unlawfully obtained evidence and whether there is a common law defence of entrapment. These cases used American "due process" and other "constitutional rights" cases to assist in deciding whether the same or analogous common law rights existed in Australia.

Notwithstanding that the Australian Constitution does not have an express "due process" clause such as those contained in the Fifth and Fourteenth Amendments to the American Constitution, the High Court has been able to rely on common law rights to produce a similar effect. Some judges have gone so far as to say that the common law right to a fair trial is entrenched in the Constitution by the notion of separation of judicial power from executive and legislative power.

In Dietrich's case, the appellant sought to rely on the "due process" clauses of statute 42 Edw. III c. 3 passed in 1368 (which still applied in Victoria) and the International Covenant on Civil and Political Rights (which Australia has ratified, but which has not been incorporated into domestic law), together with analogies from American case law to expand the common law rights of accused persons in criminal trials to include the right to counsel.

In rejecting the analogy with American cases, Mason CJ and McHugh J noted the effect of the Fifth and Fourteenth Amendments and also the way in which those rights had developed in America. They noted that "the court would be logically driven to decide whether such a right to counsel entails the right to the 'effective assistance' of counsel, as it is called in the United States". Criticising this development, they questioned how such a right could possibly be monitored by the trial judge. Thus they used a problem that had been identified with the American system to reject the applicability of this rule in Australia.

Deane J was more prepared to consider the American cases as being analogous and of assistance. He said, "I would echo the conclusion of the United States Supreme Court in Gideon v. Wainwright 'reason and reflection require us to recognize that in our adversary system of criminal justice, any person haled into court, who is too poor to hire a lawyer, cannot be assured a fair trial unless counsel is provided for him.' " Deane J said:

Toohey J supported arguments concerning the scope of a fair trial by reference to American cases, notwithstanding that he said there was nothing directly comparable to the American "due process" clauses in Australia, and that as a result, there is no absolute right to counsel.

Gaudron J, like Deane J, took a broader view of the scope of a fair trial, and relied upon American cases, while recognising that they operated in a different context, to demonstrate that "at least insofar as serious offences are concerned, legal representation, where it is desired, is essential for a fair trial."

As Deane and Gaudron JJ noted, American cases contain a large amount of potentially useful material concerning the scope of the right to a fair trial, and should not be discounted as not applicable on the basis of the Australian lack of a Bill of Rights.

In Ridgeway's Case, Mason CJ, Deane and Dawson JJ, while finding that there was no common law defence of entrapment in Australia, preferred the reasoning of minority opinions in a number of United States Supreme Court cases to support their finding that there was, instead, a judicial discretion to exclude evidence of an illegally procured offence. Thus, while entrapment was not a defence that could be put to a jury (as is the case in America), they held that the trial judge had a discretion whether evidence of the entrapment offence would be excluded in a particular case on public policy grounds, similar to the Bunning v. Cross discretion to exclude illegally obtained evidence.

Brennan J concurred and quoted from Bunning v. Cross where Stephen and Aickin JJ had quoted Holmes J of the US Supreme Court, saying: "In appropriate cases it may be 'a less evil that some criminals should escape than that the Government should play an ignoble part'."

Even in dissent, McHugh J quoted from the same dissenting American judges' opinions to support his position that a prosecution should not be stayed merely because the law enforcement authorities have done more than provide an opportunity for the commission of an offence.

The use of American cases by the judges in this instance was to examine the basis of the American rule, consider the reasoning used by the majority and minority judges, and accept that which the High Court judges found to be the more convincing position. This use of American cases opens up the scope for counsel not only to refer the court to cases in which an American court has supported a particular argument, but also those in which there was a distinguished minority opinion in support.

Marion's Case concerned the question whether a decision to sterilise an intellectually disabled female minor fell within the ordinary scope of parental powers. There had been conflicting decisions of Australian courts on the issue, which involved social, moral, and public policy considerations-just the type of case that invites innovation and appears ideal for recourse to comparative law. Indeed, the Court looked to New Zealand, English, Canadian and American (including Indiana, New Jersey, New York, Washington, Massachusetts, and US Supreme Court) cases for assistance.

The majority (Mason CJ, Dawson, Toohey and Gaudron JJ), applied much of the reasoning in American cases to non-therapeutic sterilisations notwithstanding that they acknowledged differences between the social and legal histories in Australia and America and that the American cases were based, among other things, on the constitutionally guaranteed right to privacy. They considered that this right "was allied with, or … derived from," common law principles of bodily inviolability. In support of this proposition, they quoted with approval Cardozo J, who said, "Every human being of adult years and sound mind has a right to determine what shall be done with his (sic) own body; and a surgeon who performs an operation without his (sic) patient's consent commits an assault."

As Davies and Cowen indicate, this "case illustrates [that] the mere existence of different political, social or economic environments does not require rejection of a foreign decision as a source of persuasive authority."