§1. From among the members of the presbyteral council and in a number not less than six nor more than twelve, the diocesan bishop freely appoints some priests who are to constitute for five years a college of consultors, to which belongs the functions determined by law. When the five years elapse, however, it continues to exercise its proper functions until a new college is established.
§2. The diocesan bishop presides over the college of consultors. When a see is impeded or vacant, however, the one who temporarily takes the place of the bishop or, if he has not yet been appointed, the priest who is senior in ordination in the college of consultors presides.
§3. The conference of bishops can establish that the functions of the college of consultors are to be entrusted to the cathedral chapter.
§4. In an apostolic vicariate and prefecture, the council of the mission mentioned in can. 495, §2 has the functions of the college of consultors unless the law establishes otherwise.
Source: Code of Canon Law (Vatican.va)