(1) The Attorney - General shall not authorize a payment under this Act in respect of a costs certificate referred to in section 15 unless he or she is satisfied, or is entitled under subsection (2) of this section to presume, that the certificate will not be vacated under that section.
(2) For the purposes of this section, where:
(a) there has been no appeal, or application for leave to appeal, against the judgment in the Federal appeal to which a costs certificate referred to in subsection (1) relates by the respondent an appeal by whom could result in the vacation of the certificate; and
(b) the Attorney - General has been given:
(i) notice in writing by that respondent that he or she does not intend to appeal against that judgment; or
(ii) in the case of a certificate granted to an appellant to the appeal--notice in writing by the appellant that the appellant has no reason to believe that that respondent will appeal against the judgment;
the Attorney - General is entitled to presume that the certificate will not be vacated.
(3) Where:
(a) a notice referred to in subparagraph (2)(b)(i) or (ii) has been given by, or in relation to, a respondent to a Federal appeal;
(b) an amount has been paid under this Act to a person who has been granted a costs certificate in respect of the appeal that would not have been paid but for that notice; and
(c) that respondent appeals, or seeks leave to appeal, against the judgment in the appeal;
the person so paid shall, upon demand in writing by the Attorney - General or a delegate of the Attorney - General, served on the person, either personally or by post, repay that amount to the Commonwealth within such period, not being less than 7 days, as is specified in the demand and, if the amount is not repaid within that period, the Commonwealth may recover the amount by action in a court of competent jurisdiction as a debt due to the Commonwealth.
(4) For the purpose of the application of section 29 of the Acts Interpretation Act 1901 to the service by post on a person of a demand under subsection (3), such a demand posted as a letter addressed to the person at his or her last address known to the person making the demand shall be deemed to be properly addressed.