The Undue Influence of ‘Non-Australian’ Undue Influence Law on Australian Undue Influence Law: Has Johnson v Buttress Been Overruled, Sub Silentio?

The judgments of the plurality and Gordon J in the recent High Court decision of Thorne v Kennedy [2017] HCA 49 have undoubtedly altered the prior law relating to undue influence in Australia. But the most significant alterations, which are twofold, are both unacknowledged and unsupported by justificatory reasons. First, undue influence is presented as a single concept not having different forms, or involving different principles, across the traditional categories or ‘classes’ of undue influence. Accompanying that is surreptitious abandonment of the ‘fiduciary’ explanation for the second, ‘relational’ category of undue influence, prominent in antecedent authorities such as Johnson v Buttress. This is demonstrated, in particular, by the unacknowledged and unexplained evaporation of the ‘prophylactic’ function and content of the traditional ‘presumption’ of undue influence. But nowhere do their Honours openly address and credibly respond to the conventional rationale — the generic policy foundations — that originally motivated the strict fiduciary regulatory regime in those cases where the presumption traditionally operated. Second, as a single concept, undue influence is, in stark contrast to unconscionable dealing, rationalized as a ‘plaintiff-sided’, ‘impaired-consent’ ground of relief. Although prior dicta existed to support such an outlook on undue influence, those dicta, themselves of dubious lineage, were accepted in Thorne without pause or explanation, and certainly without acknowledgment of a strong current of senior judicial opinion to the contrary, both domestically and abroad. We are left, then, in the wake of Thorne, with an unexplained disjunctive rationalization of two equitable exculpatory doctrines that are nevertheless acknowledged, presumably not disingenuously, to be ‘closely related’. This does not augur well for the logical taxonomization of those sibling doctrines, both as between themselves and relative to other exculpatory categories that equally function to discipline the abuse of unofficial power–vulnerability relationships or encounters in connection with bilateral transactions.

Professor Bigwood is a Professor of law at the TC Beirne School of Law, The University of Queensland. His principal teaching and research interests lie in the areas of contract and property law. He was formerly a Senior Solicitor and Acting Principal Solicitor with the Federal Attorney-General's Department in Canberra (Office of Commercial Law).He has published widely in leading international journals on subjects within contract, equity and property law, and he has been a keynote speaker at international conferences on contract law. His publications include: Legal Method in New Zealand (Butterworths, 2001); Exploitative Contracts (Oxford University Press, 2003) (awarded the JF Northey Memorial Book Award for 2003); The Statute: Making and Meaning (LexisNexis, 2004); Public Interest Litigation: The New Zealand Experience in International Perspective (LexisNexis, 2006); The Permanent New Zealand Court of Appeal: Essays on the First 50 Years (Hart Publishing, 2009); Contract as Assumption: Essays on a Theme (by Brian Coote) (Hart Publishing, 2010); The Law of Remedies: New Directions in the Common Law (Irwin Law, 2010) (with Jeff Berryman); and Cheshire & Fifoot, Law of Contract (10th Australian edition, 2012) (with Nick Seddon). Professor Bigwood was formerly the General Editor of the New Zealand Universities Law Review, and was Editor of the New Zealand Law Review 2002-2008. He is currently a member of the editorial boards of the New Zealand Universities Law Review and the Journal of Contract Law.

About Australian Centre for Private Law Events

The mission of the ​Australian Centre for Private Law is to foster the development and understanding of the private law through advanced theoretical, doctrinal, empirical and historical research, and the dissemination of that research through education and professional outreach. By supporting the work of its Fellows, the ACPL seeks to promote research in all areas of private law and to establish itself as a research centre of national and international importance. The core initiatives of ACPL are:

Research: To advance a deeper understanding of the structure, principles and policies of the private law through advanced theoretical, comparative, and empirical analysis.

Education: To promote, facilitate and disseminate the results of that research for the benefit of Australia’s social and economic fabric.

Professional Outreach: To engage the judiciary and members of the legal profession in discussion about the values, goals and methods of private law and the respective roles of the judiciary, the legal profession and the academy in the interpretation and reform of private law.

The ACPL embraces all branches of private law, including the law of contract, torts, trusts, equity, property, unjust enrichment, including theoretical and jurisprudential dimensions and contextual applications thereof.


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