First Subcommission--Criminal Acts
- President: W. F. Massey (British Empire)
- United States of America: Mr. James Brown Scott
- British Empire: W. F. Massey
- France: André Tardieu
- Alternate: Captain Masson
- Greece: Nicolas Politis
- Japan: Adatci
Second Subcommission--Responsibility of the Authors of the War
- President: Sir Ernest Pollock (British Empire)
- British Empire: Sir Gordon Hewart or Sir Ernest Pollock
- France: F. Larnaude
- Italy: A. Scialoja
- Alternates: A. Ricci-Busatti and Gustavo Tosti
- Belgium: Rolin-Jaequemyns
- Serbia: Slobodan Yovanovitch
- Alternates: Koumanoudi and A. Novacovitch
Third Subcommission--Violation of the Laws and Customs of War
- President: Robert Lansing (United States of America)
- United States of America: Robert Lansing
- Italy: d'Amelio
- Japan: H. Nagaoka
- Alternate: Sakutaro Tachi
- Poland: Constantin Skirmunt
- Alternate: Léon Lubienski
- Roumania: S. Rosental