He was in private practice in St. Louis, Missouri, from 1902 to 1935, also working as a United States Collector of Internal Revenue from 1914 to 1922.
[1] Moore was nominated by President Franklin D. Roosevelt on May 20, 1935, to a seat on the United States District Court for the Eastern District of Missouri vacated by Judge Charles Breckenridge Faris.
Moore was confirmed by the United States Senate on May 28, 1935, and received his commission the following day.
He served as Chief Judge from 1948 to 1959, and assumed senior status on January 19, 1962.
He continued to serve as a senior judge until his death on November 5, 1962.