Anglo American Investments Pty Ltd v Deputy Commissioner of Taxation

Anglo American Investments Pty Ltd (the applicant) sought leave to appeal from a decision of the primary judge who had struck out an amended defence in debt recovery proceedings brought by the Deputy Commissioner of Taxation (the respondent). The applicant's amended defence pleaded "conscious maladministration" by the respondent. The appeal concerned the jurisdiction of the Court in taxation debt recovery proceedings and the effect of provisions of the *Income Tax Assessment Act 1936* (Cth) and the *Taxation Administration Act 1953* (Cth).

The central legal issue before the Court of Appeal was whether the applicant's amended defence, alleging "conscious maladministration" by the respondent, disclosed a real question of law fit for determination on appeal, or whether it was so manifestly untenable that it ought to be struck out. This involved considering the combined effect of section 175 of the *Income Tax Assessment Act 1936* and section 350-10(1) of Schedule 1 of the *Taxation Administration Act 1953*, which generally prevent courts from inquiring into the validity of assessments.

The Court of Appeal held that the applicant's amended defence was an impermissible collateral attack on the validity of the assessments. It reasoned that section 175 of the *Income Tax Assessment Act 1936* and section 350-10(1) of the *Taxation Administration Act 1953* operate to prevent a taxpayer from challenging the validity of an assessment in debt recovery proceedings, except in very limited circumstances not applicable here. The pleading of "conscious maladministration" did not fall within any recognised exception to these exclusionary provisions and was therefore an abuse of process.

Consequently, the Court of Appeal refused the application for leave to appeal and ordered the applicant to pay the respondent's costs.