Morse used his legal skills with extraordinary effectiveness as a labor arbitrator, a position that eventually consumed Morse’s time and energy to the point where he resigned as dean. Morse’s mission as an arbitrator was to uphold what he saw as the sanctity of the contract, the rule of law in the field of labor relations. Deeply committed to fairness and justice, he was popular both with unions and employers. He later served on the National War Labor Board, a national twelve-person group that negotiated with both labor and industry leaders to insure the production of materials necessary for the Second World War.