Judge Gary was born and educated at Cokesbury. His two brothers served as Judges with him: Chief Justice Eugene Blackburn Gary and Frank B. Gary of the Eighth Judicial Circuit.
Ernest Gary studied law under his uncle, William T. Gary, and in 1880 entered practice as the partner of another uncle, General Martin Witherspoon Gary, at Edgefield. He served as a member of the South Carolina Legislature from 1886–92 and was Chairman of the House Judiciary Committee. He served as Chairman of the Edgefield County Democratic Committee, was a Presidential elector at-large in 1892, and was elected Judge of the Fifth Judicial Circuit in December of that same year. He sat several times as a Special Associate Justice on the South Carolina Supreme Court.
A diligent, careful lawyer, he was a conscientious judge noted as prompt in deciding equity cases. Firm but considerate when presiding, he knew no master but the law.
True friend, able lawyer and an esteemed Judge.