[1] In 1914, he was appointed to a seat on the Alabama Supreme Court vacated by the elevation of C. J. Anderson to chief justice.
Gardner then won election to the remainder of the term, and was reelected as a Justice in 1922, 1928, and 1934.
In 1940, Governor Frank M. Dixon elevated Gardner to Chief Justice, and he won election to that office later in 1940, winning reelection again in 1946.
[1] In an anti-miscegenation case ruling in Alabama, Gardner stated that "It is reprehensible enough for a white man to live in adultery with a white woman thus defying the laws of God and man, but it is more so, and a much lower grade of depravity, for a white man to live in adultery with a Negro woman."
Gardner died in a hospital in Montgomery, Alabama, at the age of 76, following a period of ill health, and six months after the death of his wife.