Ibbotson and Ibbotson (Child support)

This matter concerned a review by the Tribunal of a child support administrative assessment, with Mr Ibbotson and Ms Ibbotson participating in the hearing. The core dispute revolved around whether an income estimate used in the child support assessment should be backdated. The Tribunal considered extensive documentation from Child Support and sworn evidence from both parties, applying the provisions of the *Child Support (Assessment) Act 1989* (the Act) and the *Child Support (Assessment) Regulations 2018* (the Regulations).

The legal issues before the Tribunal were whether the Registrar had correctly applied section 58 of the Act in making an income estimate for Mr Ibbotson, and subsequently, whether section 58A of the Act required the administrative assessment to be amended retrospectively or prospectively based on a later ascertained adjusted taxable income. The Tribunal also considered the application of government policy as outlined in the Guide to Social Policy Law – Child Support Guide, noting that while not bound by policy, it should be taken into account if consistent with the legislation.

The Tribunal's reasoning focused on the interpretation of section 58A of the Act, which governs the amendment of administrative assessments when a parent's adjusted taxable income is subsequently ascertained or a later determination is made under section 58. The Tribunal noted that section 58A(2) provides for retrospective amendment if certain conditions are met, including if the parent could still lodge their tax return by the required date, or if the subsequently ascertained amount is higher than the initially determined amount. If these conditions are not met, section 58A(3) dictates a prospective amendment. The Tribunal affirmed the decision under review, indicating it found the application of the relevant legislative provisions to be correct.