Expenditure not to be allowed as deduction.
18. (1) In computing the total income of a person for any financial year, the following shall not be allowed as a deduction, namely:—
(a) any expenditure, attributable to income which is not included in the total income under the Sixth Schedule, determined in accordance with such method as may be prescribed;
(b) any expenditure attributable to any income from special sources;
(c) any expenditure which has been allowed as a deduction in any other financial year;
(d) any expenditure incurred for an activity which is an offence or which is not permissible by law;
(e) any provision made for any liability, if it remains unascertained by the end of the financial year; and
(f) any unexplained expenditure referred to in clause (q) of sub-section (2) of section 58.
(2) Any amount allowed as a deduction under any provision of this Code shall not be allowed as a deduction under any other provision of this Code.
(3) The provisions of this section shall apply notwithstanding anything in any other provisions of this Chapter.