English courts have not yet had the opportunity to consider fully what would constitute undue influence in the context of a prenuptial agreement. 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.
Even if prenups are not made legislatively binding in the near future, the courts since Radmacher (Formerly Granatino) v Granatino  UKSC 42,  2 FLR 1900 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  HCA 49 will be of interest and importance for lawyers in England, Wales and Northern Ireland. Sharon Thompson's article in the April 2018 issue of Family Law argues that as well as providing guidance on the operation of undue influence in the context of prenups, Thorne crucially opens up the possibility for a broader range of circumstances to be taken into account when giving effect to such agreements. Indeed, the High Court of Australia’s approach can provide inspiration to courts elsewhere showing how agreements can be assessed contextually, without resorting to a paternalistic approach that undermines individuals’ agency in practice.
The full version of this article will appear in the April 2018 issue of Family Law.