Mordan and Child Support Registrar (Child support)

The Administrative Appeals Tribunal (AAT) considered the dispute between Mordan and the Child Support Registrar concerning the determination of a new percentage of care for a child. The applicant, Mordan, sought to have the date of effect for this new care percentage determination altered.

The primary legal issue before the Tribunal was to determine the correct date from which a new percentage of care should take effect, particularly when the Registrar had made a decision to change the care percentage. This involved interpreting the relevant provisions of the *Child Support (Registration and Collection) Act 1988* (Cth) and the *Child Support Assessment Act 1989* (Cth) concerning the establishment and retrospective application of care percentages.

Deputy President Walsh applied the principles established in previous case law, particularly concerning the interpretation of "likely pattern of care" and the circumstances under which a new care percentage determination could be backdated. The Tribunal considered the evidence presented regarding the actual care arrangements and the Registrar's decision-making process. The Deputy President found that the Registrar's decision to set the date of effect was not in accordance with the law.

Consequently, the Tribunal set aside the decision under review and substituted its own decision, ordering that the new care percentage determination take effect from a date earlier than that initially determined by the Registrar.