Gartrell passed the state bar in 1842 and began the practice of law in Washington.

[1] Gartrell served as the solicitor general of the northern judicial circuit from 1843 until 1847 when he was elected to the Georgia House of Representatives.

[1][2] He resigned from his second term in 1861 to form the Seventh Regiment of the Georgia Volunteer Infantry in the Confederate army during the Civil War.

After the death of his first wife, Gartrell married Antoinette Phoebe Burke (1834-1882).

After the war, Gartrell served as a member of the State constitutional convention in 1877.