25. Staff  26. Class-child ratio  ( c )  a person qualified to practise in Botswana as a medical practitioner, appointed by the  President by instrument i n writing under his or her hand. ( b )  the Attorney-General; and  ( a )  the Vice-President or a Minister appointed by the President by instrument in writing  under his or her hand;  (i)  in the case of a person who, at the date of his or her appointment, was the  Vice-President or a Minister, if he or she ceases to be the Vice -President or a Minister; or (ii)  if the President, by instrument in w riting under his or her hand, so directs. (1) There shall be an Advisory Committee on the Prerogative of Mercy which shall consist  of-  (2) A member of the Committee appointed under subsection (1)( a ) or ( c ) of this section  shall hold his or her seat thereon for such period as may be specified in the instrument by which  he or she was appointed:  Provided that his or her seat shall become vacant -  (3) The Committee shall not be summoned except by the authority of the President who  shall, as far as is practicable, attend and preside at all meetings of the Committee, and, in the  absence of the President, themember of the Committee appointed under subsection (1)( a ) of this  section shall preside.  (4) The Committee may act notwithstanding any vacancy in its membership and its  proceedings shall not be invalidated by the presence or participation of any person no t entitled to  be present at or to participate in those proceedings. (5) Subject to the provisions of this section, the Committee may regulate its own  procedure. 55.  Functions of Advisory Committee on Prerogative of Mercy  (1) Where any person has been sentenced to death for any offence, the President shall  cause a written report of the case from the trial judge, together with such other information derived  from the record of the case or elsewhere as he or she may require, to be considered at  a meeting  of the Advisory Committee on the Prerogative of Mercy; and after obtaining the advice of the  Committee he or she shall decide whether to exercise any of his or her powers under section 53 of  this Constitution.  (2) The President may consult with  the Committee before deciding whether to exercise  any of his or her powers under the said section 53 in any case not falling within subsection (1) of  this section.  56.  Constitution of offices CHAPTER V  Parliament  (ss 57-94) PART I  Composition  (ss 57-70)  57.  Parliament Subject to the provisions of this Constitution and  of any Act of Parliament, the powers of  constituting and abolishing offices for Botswana shall vest in the President. There shall be a Parliament of Botswana which  shall consist of the President and a  National Assembly.  58.  Composition of National Assembly  (1) The President shall be  ex-officio  a member of the National Assembly, and shall be  entitled to speak and to vote in all proceedings of the  National Assembly.  Copyright Government of Botswana (2) In addition to the President the National Assembly shall consist of - 