Tan v Child Support Registrar

The case of *Tan v Child Support Registrar* concerned appeals from decisions of the Social Security Appeals Tribunal (SSAT) and an application for judicial review, heard by Judge Riethmuller. The central dispute revolved around the reconciliation of the costs of raising children with the Costs of Children Tables, and whether principles of issue estoppel or the doctrine of *functus officio* applied to decisions made by the Child Support Registrar or the SSAT.

The court was required to determine whether the SSAT had erred in its application of the Costs of Children Tables to the specific circumstances of the parties. Furthermore, the court had to consider whether the doctrine of issue estoppel prevented the Child Support Registrar or the SSAT from revisiting or making new decisions on matters previously determined. The court also had to assess whether the Child Support Registrar was *functus officio*, meaning their authority to act in relation to a particular matter had ceased.

Judge Riethmuller dismissed the appeals from the SSAT decisions and the application for judicial review. The reasoning likely involved a determination that the SSAT had correctly applied the relevant legislation and tables, and that the principles of issue estoppel and *functus officio* did not preclude the Registrar or SSAT from making the decisions under review in the circumstances presented. The court found no grounds for judicial review.

Consequently, the appeal with respect to SSAT appeal [1] was dismissed, as was the appeal with respect to SSAT appeal [2]. The application for judicial review filed on 15 June 2012 was also dismissed, and there were no orders as to costs.