Albert Barnes Commentary 2 Samuel 20:24

"and Adoram was over the men subject to taskwork; and Jehoshaphat the son of Ahilud was the recorder;" — 2 Samuel 20:24 (ASV)

Adoram - Not mentioned before by name or office. Apparently, therefore, the office was not instituted until the latter part of David’s reign, and its duties probably were the collection of the tribute imposed upon vanquished nations, or the command of the forced levies employed in public works. Adoram was stoned to death in the beginning of the reign of Rehoboam (1 Kings 12:18).