Born on August 23, 1891, in
Lexington, Virginia, Prettyman went to school in Washington, D.C. and
Baltimore, Maryland. He worked as an evenings and weekends sports correspondent for
The Baltimore American, and a police reporter for
The Baltimore Sun, from 1905 to 1907. He received a Bachelor of Arts degree in 1910 from
Randolph–Macon College and an
Artium Magister degree in 1911 from the same institution. He received a
Bachelor of Laws in 1915 from
Georgetown Law. He entered private practice in
Hopewell, Virginia from 1915 to 1917. Prettyman was a
United States Army Captain during
World War I from 1917 to 1919. Although he was commissioned as an artillery captain, he also served as a judge advocate where he oversaw hundreds of courts-martial. He was a special attorney for the
Bureau of Internal Revenue of the
United States Department of the Treasury in Washington, D.C., and New York City, New York from 1919 to 1920. He was in private practice in Chicago, Illinois, Washington, D.C., and New York City from 1920 to 1933. Prettyman was general counsel for the Bureau of Internal Revenue from 1933 to 1934. He was corporation counsel for Washington, D.C., from 1934 to 1936. He was in private practice in Washington, D.C., and
Hartford, Connecticut, from 1936 to 1945. ==Federal judicial service==