Dorsey the third child of three children born to Nicholas Brodie Hardeman and Joanna Tabler. Dorsey studied at the Freed Hardeman College, co-founded by his father N.B. Hardeman and A.G. Freed in 1908. Dorsey developed tuberculosis and relocated to Gainesville, Fl for a change of climate, there he attended the University of Florida and earned his LLB from Vanderbilt University. He returned to Tennessee, then moved to Texas in 1932, he became very active in government, business and legal affairs. He was elected mayor in 1936 of San Angelo and in 1938 he was elected to the House of Representatives and served two terms, (1939-1942) before joining the United States Army Air Corps. After his military service he was elected to the State Senate serving for twenty-two years from 1947-1969. The Senator was a dscendant of General William P. Hardeman and Bailey Hardeman, signers of the Texas Declaration of Independence in 1836. He owned the historic San Angelus Hotel in San Angelo, had ranching and farming interests in Texas and Colorado, owned and operated a title company in West Texas. He was a member of many organizations, including hereditary membership in Sons of the American Revolution, Sons of the Republic of Texas, Knights of San Jacinto, Sons of Confederate Veterans, Order of Stars and Bars, the Baronial Order of Magna Charta, Huguenot Society, Knights of Malta, an honorary membership in the Greek order of St. Denis of Zante and was a lifetime member of the Texas State Historical Association. He was a member of the American Legion, State bar of Texas, the Travis County and Tom Green County Bar Associations, and was a member of the Church of Christ in Austin.

Dorsey was preceded in death by his father, mother and two sisters.

He is survived by his widow, Geneva; sons and daughters-in-law, Mark and Francine of Sonora, Texas and Bryan and Rebecca of Austin, Texas; grandchildren, William Bryan Hardeman and Genny and Joy Hardeman of Austin; a niece, Joanne Bradshaw of Atlanta, Georgia; nephews, Nicholas Powers of Memphis, Tennessee and Joe Hardeman Foy of Houston, Texas.