17. Since the purpose of the Conferences of Bishops is to provide for the common good of the particular Churches of a territory through the collaboration of the sacred pastors to whose care they are entrusted, every individual Conference is to include all the diocesan Bishops of the territory and those who in law are equivalent to them, as well as coadjutor Bishops and the other titular Bishops who exercise a special task entrusted to them by the Holy See or by the Episcopal Conference itself.(⁶⁶) In the plenary meetings of the Episcopal Conference, the deliberative vote belongs to diocesan Bishops and to those who are equivalent to them in law, as well as to coadjutor Bishops; and this by reason of the law itself. The statutes of the Conference cannot provide otherwise.(⁶⁷) The President and Vice-President of the Episcopal Conference must be chosen only from among the members who are diocesan Bishops.(⁶⁸) As regards auxiliary Bishops and other titular Bishops who are members of the Episcopal Conference, the statues of the Conference should determine whether their vote is deliberative or consultative.(⁶⁹) In this respect, the proportion between diocesan Bishops and auxiliary and other titular Bishops should be taken into account, in order that a possible majority of the latter may not condition the pastoral government of the diocesan Bishops. However, it is appropriate that the statutes of Episcopal Conferences allow for the presence of Bishops emeriti, and that they have a consultative vote. Particular care should be taken to enable them to take part in some study Commissions, when these deal with issues in which a Bishop emeritus is particularly competent. Given the nature of the Episcopal Conference, a member's participation in the Conference cannot be delegated to someone else.