Jamieson, Fausset and Brown on 2 Chronicles 19:8

8. set of the Levites ... priests, and of the chief of the fathers of Israel--A certain number of these three classes constituted a supreme court, which sat in Jerusalem to review appellate cases from the inferior courts. It consisted of two divisions: the first of which had jurisdiction in ecclesiastical matters; the second, in civil, fiscal, and criminal cases. According to others, the two divisions of the supreme court adjudicated: the one according to the law contained in the sacred books; the other according to the law of custom and equity. As in Eastern countries at the present day, the written and unwritten law are objects of separate jurisdiction.