Below is a list of FDNY Fire Commissioners and CODs, and their tenures, from 1865-2002, from Paul H. I believe Chief Don Ruland was the last COD who advanced to the position by promotion in 1994. All CODs have been up-thru-the-ranks FDNY members.
Commissioners have had diverse backgrounds. Some have been former FDNY CODs or members with leadership experience.
Examples of Fire Commissioners with FDNY backgrounds:
Bonner - COD
Dorman - COD
McElligott - COD
Walsh - COD
Thompson - war veteran and judge
Scott - Chief Fire Marshal
Lowery - successful Deputy Fire Commissioner
O'Hagan - COD
Beekman - experienced Assistant Chief
Rivera - experienced Assistant Chief
Feehan - COD
Von Essen - President UFA
Cossano - COD
Nigro - COD
Others primarily had backgrounds as senior-level government or private sector leaders with political, legal or budgetary expertise.