The High Court's increasing use of American cases has demonstrated its greater independence from English legal authority. This has occurred at the same time as English law is being more heavily influenced by continental European law. The effect of the Australia Act 1986 (Cth) as a final declaration of independence for the High Court and a basis for constitutional notions of popular sovereignty has been nearly as important as the effect of the Engineers' Case in 1920. Both events changed the Court's understanding of fundamental Constitutional values, which, in turn, accelerated a change in attitude regarding the usefulness or otherwise of American cases.
Davies and Cowen have suggested that Australian judges are generally ill equipped and rarely in a position to discover the background of American authorities, and are dependent on the counsel that appear before them to provide them with sufficient accurate information about the environment in which a particular American case operates in order to assess whether or how much an American decision, or the reasoning in it, is applicable in the matter before the court. They note: "In the absence of a reliable system of determining the influence of legal, social or political factors in the decision or reasoning of a foreign court this task will remain a risky one." The increasing trend in the High Court of citing American cases will inevitably mean that such cases will be more frequently cited by counsel to lower courts, which do not have the resources or expertise of the High Court. This will increase the pressure on judges and counsel to gain a better understanding of American law and context.
In 1987, Lockhart J of the Federal Court said:
"The use of overseas authorities, in particular those from the USA and Canada, as a guide to decisions in Australian cases is becoming increasingly common and perhaps understandably so. But on a practical level recurrent reference to overseas case law inevitably puts more pressure on libraries, both professional and scholastic, to subscribe to the series of reports in question."
While that is undoubtedly true, it is perhaps not as big a problem as it was in 1987. Access to American case law via CD-Rom and the Internet has made it more readily available to Australian lawyers, and easier to search. However, it also poses a significant threat to the use of American cases in Australian courts if it is mis-used by lawyers. Indiscriminate and inappropriate use of American cases to bolster a doubtful argument may set some judges against American cases generally. Therefore, there is a need for comparative American-Australian law to be offered, at least at post-graduate level, in Australian law schools to assist barristers and judges cope with this new development in Australian law.
While the Australian High Court has been ready to borrow from the United States Courts, a recent commentator has noted, with regret, that US courts do not consider stepping into the jungle of foreign case law:
"American jurists are disinclined to interest themselves in foreign example for the same reason that scientists at American medical schools are disinclined to investigate the merits of medicine as it is practised among the witch doctors of the Amazonian rain forest. They operate on the assumption that the foreigners have nothing to teach. But whereas the shortcomings of Amazonian medicine have been objectively verified, the disdain for [foreign] law rests upon a witch's brew of ignorance, prejudice, and venality. Fortified in the lucrative fool's paradise that they inhabit, American legal professionals have little incentive to open their eyes to the disturbing insights of comparative example."
Perhaps, with the greater frequency of use of American cases by the High Court and the internationalisation of Australian law, the American courts might see the benefit of considering the High Court's discussion of common legal issues given that its discussion of the American cases will be an indication of relevance to the American situation. If so, the "convergence of constitutions" might presage further convergence in other areas of law, with give and take on both sides of the Pacific.