He received his early education from the public schools of Lonaconing.
In 1892, he graduated from Washington & Jefferson College, and proceeded to study law with his cousin David W. Sloan in Cumberland, Maryland.
[1] After being admitted to the Bar, Sloan entered into private law practice in Cumberland, where he worked from 1895 to 1926.
He was promoted to chief judge of the Court of Appeals in 1943, where he served until 1944.
[2] Sloan also served as President of the Maryland Bar Association in 1932, and as vice-chair of the State War Ballot Commission from 1950 until his death in 1962.