Patterson was nominated by President Herbert Hoover on April 24, 1930, to a seat on the United States District Court for the Southern District of New York vacated by Judge Thomas D. Thacher. He was confirmed by the United States Senate on May 13, 1930, and received his commission the same day. His service terminated on March 22, 1939, due to his elevation to the Second Circuit. Patterson was nominated by President Franklin D. Roosevelt on February 9, 1939, to a seat on the United States Court of Appeals for the Second Circuit vacated by Judge Martin Thomas Manton. He was confirmed by the Senate on March 20, 1939, and received his commission on March 21, 1939. His service terminated on July 30, 1940, due to his resignation.
War Department service
Patterson served as a United States Assistant Secretary of War in 1940. He served as United States Under Secretary of War from 1940 to 1945. He was instrumental in the mobilization of the armed forces preparatory to and during World War II. President Harry S. Truman appointed Patterson as United States Secretary of War in 1945. Truman initially was set to offer Patterson a seat on the United States Supreme Court which was left vacant by Justice Owen J. Roberts, however, with the resignation of Henry L. Stimson, Patterson instead became the Secretary of War. Patterson advocated unifying the armed services and having a single chief of staff. Steps to this effect were begun by the National Security Act of 1947 and revised several times, finally by the Goldwater-Nichols Act of 1986. Patterson worked to promote more black participation and promotion with in the military, specifically during the late stages of World War II. He was instrumental in creating an African-American fighter group, known now as the Tuskeegee airmen. While sympathetic to black grievances, aspirations, and recommendations he was concerned that radical change would impede military preparedness during war. After the war the "Board for Utilization of Negro Manpower". released a report, "Utilization of Negro Manpower in the Postwar Army Policy", in April 1946. that was signed off by Patterson: it recommended the retention of segregation, as that was a policy external to the military, but that the military introduce equal opportunity, as that would be the best use of military manpower. Patterson served until 1947.
Later career
After declining an offer by President Truman to be reappointed to his former judgeship, Patterson returned to private practice in New York City from 1947 to 1952, Later he became the President of the Association of the Bar of the City of New York, and the President of the Council on Foreign Relations.
Personal life
On January 3, 1920, Patterson married Margaret Tarleton Winchester ; they had four children: Robert P. Patterson, Jr., Aileen W. Patterson, Susan H. Patterson and Virginia D. Patterson. Robert P. Patterson Jr. was a federal judge in the Southern District of New York, until his death in 2015. Patterson housed William L. Marbury Jr., at his Georgetown home. After the war, he recommended Marbury to succeed him at the United Nations; upon advice from Alger Hiss, Marbury declined.
In 2012, the University of Tennessee Press published The World War I Memoirs of Robert P. Patterson: A Captain in the Great War, edited by J. Garry Clifford. In 2014, the University of Tennessee Press published his previously unpublished 1947 memoir Arming the Nation for War, with a foreword by Robert M. Morgenthau, former Manhattan district attorney, and edited by Brian Waddell, associate professor at the University of Connecticut.
The World War I Memoirs of Robert P. Patterson: A Captain in the Great War
Arming the Nation for War: Mobilization, Supply, and the American War Effort in World War II