A particular council, for its own territory, takes care that provision is made for the pastoral needs of the people of God and possesses the power of governance, especially legislative power, so that, always without prejudice to the universal law of the Church, it is able to decide what seems opportune for the increase of the faith, the organization of common pastoral action, and the regulation of morals and of the common ecclesiastical discipline which is to be observed, promoted, and protected.
Source: Code of Canon Law (Vatican.va)