Rafter and Rafter

This case concerns an application to vary or set aside a financial agreement under section 90K of the *Family Law Act 1975* (Cth). The applicant sought to have the agreement declared void or set aside on the grounds that it had become impracticable to carry out.

The primary legal issue before the court was the interpretation of the term "impracticable" within the context of section 90K(1)(b) of the *Family Law Act 1975* (Cth), and whether the circumstances presented by the applicant met this threshold for setting aside a financial agreement. This involved considering the relationship between orders for the settlement of property and maintenance orders, and the application of contractual doctrines, such as frustration, to financial agreements.

The court, drawing on authority from cases such as *Cawthorn & Cawthorn* and *Sanger & Sanger*, emphasised the importance of preserving the distinction between variable maintenance orders and permanent property settlement orders. It held that the concept of impracticability under section 90K(1)(b) is distinct from mere difficulties in enforcement arising from insolvency. The court noted that financial difficulties, including insolvency, have historically not given rise to the successful invocation of the doctrine of frustration in contract law, and this principle applies by analogy to financial agreements under the Act. The court also referred to the principles of contractual frustration as discussed in *Brisbane City Council v Group Projects Pty Ltd* and *Codelfa Construction Pty Ltd v State Rail Authority (NSW)*, highlighting that frustration occurs when a contract is rendered impossible to perform due to an unforeseen event that fundamentally alters the nature of the contractual obligation, rather than merely making it more difficult or expensive to perform.

The court found that the applicant had not established that the financial agreement had become impracticable to carry out in the sense contemplated by section 90K(1)(b). The circumstances relied upon by the applicant, relating to financial difficulties, did not meet the strict criteria for setting aside the agreement.