Thorne v Kennedy: Why Australia's decision on prenups is important for English law

There are two main reasons why the courts in England, Wales and Northern Ireland have not yet had the opportunity to consider fully what would constitute undue influence in the context of a prenuptial agreement (prenup). First, prenups are not binding under legislation here, as the court can still decide to not give effect to an agreement if it would lead to unfairness. For instance, as Lord Phillips put it in Radmacher (Formerly Granatino) v Granatino [2010] UKSC 42, [2010] 2 FLR 1900 (para 81), if the agreement would leave one of the parties in a position of real need whilst the other party enjoys a sufficiency or more. Secondly, the courts in England and Wales have avoided the issue of whether prenups have contractual status or not, and so whilst vitiating factors such as duress and undue influence are relevant to whether consent to a prenup was freely given, the court has said that pressure falling short of duress is also relevant (though in practice it has adopted a restrictive approach). But knowing when pressure will amount to undue influence in this jurisdiction is still important, not least because calls for contractually binding prenups have resurfaced in recent months (see, for example, Divorce (Financial Provision) Bill 2017-19). Even if prenups are not made legislatively binding in the near future, the courts since Radmacher have taken a fairly restrictive approach when deciding when an imbalance of power between the parties will affect the weight of a prenup on relationship breakdown. This is problematic when the autonomy of one party has been compromised by power inequalities in the relationship, and so a new approach is needed. For this reason, the ground-breaking approach of the High Court of Australia in Thorne v Kennedy [2017] HCA 49 will be of interest and importance for lawyers in England, Wales and Northern Ireland. As well as providing guidance on the operation of undue influence in the context of prenups, it crucially opens up the possibility for a broader range of circumstances to be taken into account when giving effect to such agreements