§1. It is for the diocesan bishop to govern the particular church entrusted to him with legislative, executive, and judicial power according to the norm of law.
§2. The bishop exercises legislative power himself. He exercises executive power either personally or through vicars general or episcopal vicars according to the norm of law. He exercises judicial power either personally or through the judicial vicar and judges according to the norm of law.
Source: Code of Canon Law (Vatican.va)