18. (1) Expenditure that is—
(a) in excess of the amount specifically appropriated for expenditure of that kind; or
(b) not provided for by any appropriation;
may be authorised by the Treasurer by instrument provided that—
(c) the need for the expenditure could not reasonably have been foreseen at the time of the passing of any of the Appropriation Acts relating to the financial year in which the expenditure is to occur; and
(d) the total expenditure authorised under this subsection in any financial year does not exceed the amount appropriated for that year for the purposes of this section.
(2) The amount appropriated for the purposes of this section for a financial year shall not exceed 1% of the total amount appropriated by all Appropriation Acts for that year.
(3) Where the Treasurer has authorised expenditure under subsection (1) during a financial year and expenditure has been incurred under that authorisation during the year, the Treasurer shall cause—
(a) a copy of the authorisation; and
(b) a statement of the reasons for giving it;
to be laid before the Legislative Assembly as soon as practicable after the end of the year.