§1. To a conference of bishops belong by the law itself all diocesan bishops in the territory, those equivalent to them in law, coadjutor bishops, auxiliary bishops, and other titular bishops who perform in the same territory a special function entrusted to them by the Apostolic See or conference of bishops. Ordinaries of another rite can also be invited though in such a way that they have only a consultative vote unless the statutes of the conference of bishops decree otherwise.
§2. Other titular bishops and the legate of the Roman Pontiff are not by law members of a conference of bishops.
Source: Code of Canon Law (Vatican.va)