Mabbitt and Child Support Registrar (Child support)

Ms Mabbitt applied to the Administrative Appeals Tribunal (AAT) for an extension of time to seek a review of a child support objection decision made by the Child Support Registrar on 16 August 2018. The Registrar's decision had altered the care percentages for the parties' two children, with the effective date of this change being 27 February 2018, as special circumstances were not met to apply it earlier. Ms Mabbitt sought to extend the time to apply for a review of this specific date of effect decision, having lodged her application for an extension on 17 April 2020, approximately 581 days after the prescribed 28-day period for review had expired.

The primary legal issue before the Tribunal was whether to grant Ms Mabbitt's application for an extension of time to seek a review of the objection decision. This required the Tribunal to consider the relevant provisions of the Child Support (Registration and Collection) Act 1988 and the Administrative Appeals Tribunal Act 1975, particularly those governing applications for review and extensions of time. The Tribunal was guided by the principles established in *Hunter Valley Developments Pty Ltd v Cohen* and a range of other factors commonly considered when exercising discretion to grant an extension, including the reasons for the delay, the merits of the substantive application, potential prejudice to other parties, and overall fairness.

In its reasoning, the Tribunal found that Ms Mabbitt had not provided a satisfactory explanation for the significant delay. While acknowledging her claims of confusion regarding appeal rights and ongoing stress due to domestic violence, the Tribunal noted that the notification of the objection decision clearly indicated the 28-day review period, and she had also been verbally advised of her appeal rights. Furthermore, her delay in approaching Services Australia for an internal review suggested she had rested on her rights. The Tribunal also determined that Ms Mabbitt's substantive application had little merit, as her argument regarding the impact of the care decision on family tax benefits was not sufficient to establish special circumstances for an earlier effective date. The Tribunal also considered the prejudice to the other party, Mr A, who could reasonably expect the assessment to be final after such a lengthy delay, and the general public interest in the certainty of time limits.

Consequently, the Tribunal concluded that it would not be proper to grant the extension of time. The Tribunal refused Ms Mabbitt's application for an extension of time to seek a review of the objection decision.