Garland was born in Lynchburg, Virginia and he pursued a basic education, studied law and was admitted to the bar and commenced the practice of law. He moved to Opelousas, Louisiana in 1820 and continued the practice of his profession. Garland was elected from the Louisiana's 3rd congressional district as an Anti-Jacksonian in 1833 to the Twenty-third Congress to fill the vacancy caused by the resignation of Henry Adams Bullard. He was reelected as an Anti-Jacksonian to the Twenty-fourth Congress and as a Whig to the Twenty-fifth and Twenty-sixth Congresses, in which he served as Chairman of the Committee on Expenditures in the Department of War. Garland served in Congress from April 28, 1834, to July 21, 1840, when he resigned to accept an appointment as Judge of the Supreme Court of Louisiana, in which capacity he served, with residence in New Orleans until 1846. In 1846, he moved to Brownsville, Texas, and continued the practice of law until his death in that city in 1861; He was buried in a cemetery at Brownsville.