William Theodore Mulloy (November 9, 1892 – June 1, 1959) was an American prelate of the Roman Catholic Church.

[2] He became president of the National Catholic Rural Life Conference in 1935, and rector of St. Mary's Cathedral in 1938.

[1] He also served as superintendent of Catholic schools in the Diocese of Fargo and editor of the diocesan newspaper.

[2] On November 18, 1944, Mulloy was appointed the sixth Bishop of Covington, Kentucky, by Pope Pius XII.

Speaking to the Catholic Committee of the South in 1951, he declared that "racial justice is a moral question" and that Catholic leaders in the Southern United States "cannot remain silent," even at the expense of being labeled with "the opprobrious accusation of being 'anti-Southern.