Ex parte

The Carpathia Tin Mining Company sought an order nisi from the High Court, calling upon the Federal Commissioner of Taxation to show cause why a writ of mandamus, or similar relief, should not be issued. The company desired the Commissioner to alter its income tax assessments for the years 1917-1918 to 1924-1925, asserting these alterations were necessary to ensure the completeness and accuracy of those assessments.

The central legal issue before the court was whether a taxpayer could compel the Federal Commissioner of Taxation to exercise the power granted by section 33 of the *Income Tax Assessment Act 1915-1918* to make alterations or additions to an assessment. Specifically, the court had to determine if the Commissioner's discretion under this section was absolute when he did not believe such alterations were necessary for completeness and accuracy.

Rich J. held that the High Court would not issue a writ of mandamus to compel the Commissioner to exercise his power under section 33. His Honour reasoned that the wording of section 33(1) – "as he thinks necessary" – vested a discretion in the Commissioner, and that no one else's opinion could substitute for his own judgment on the necessity of alterations or additions. While the Commissioner was bound to act if he formed the opinion that alterations were necessary, the section did not grant a right to the taxpayer to compel him to form that opinion or to make alterations if he did not deem them necessary. This interpretation was consistent with other provisions of the Act concerning assessments and objections.

The application was refused by Rich J. and subsequently by the Full Court.