s 143 Errors and defects in assessments, notices and other documents
(1) No assessment, notice or other document purporting to be made or issued for the purposes of this Act shall be quashed or deemed to be void or voidable for want of form, or be affected by any mistake, defect or omission therein, if it is in substance and effect in conformity with this Act or in accordance with the intent and meaning of this Act and— (a) in the case of an assessment, the person assessed or intended to be assessed or affected thereby is designated according to common intent and understanding; and (b) in any other case, the person to whom it is addressed and any other person referred to therein are so designated. (2) An assessment purporting to be made or issued for the purposes of this Act shall not be impeached or affected by reason of a mistake therein as to— (a) the name of a person charged to tax; (b) the description of any income; or (c) the amount of chargeable income assessed or tax charged, and a notice of assessment purporting to be so made or issued shall not be impeached or affected by any such mistake if it is served on the person in respect of whom the assessment was made or intended to be made (or served in accordance with subsection 67(5)) and contains in substance and effect the particulars contained in the assessment. (3) Notwithstanding subsection (2), if the amount of tax charged by an assessment has been incorrectly calculated by reference to the amount of the chargeable income and the appropriate rate of tax applicable thereto, the amount of tax charged as shown in the assessment and the notice of assessment may, if the Director General so directs, be taken to be the amount of tax which ought to have been charged if it had been correctly calculated. (4) A notice of tax payable purporting to be issued for the purposes of this Act shall not be impeached by reason of a mistake therein as to the name of the person liable to pay the tax if the notice is served on that person.