John Colcock was born in 1744, the son of a sea captain who settled in Charleston. He was admitted to the practice of law, most likely having read law with a trained lawyer, in the Court of Common Pleas at Charles Town on February 12, 1767. (1) He was elected “Secretary and Correspondent” of the Charlestown Library Society in January, 1769. (2) He is mentioned by George Rogers in his Generations of the Bar as one of the first lawyers to make a reputation outside of Charleston. (3) His most famous client was Col. Isaac Hayne, who was executed by the British as a traitor. Col. Hayne had married Elizabeth Hutson, sister of Richard Hutson. No doubt the two lawyers were well acquainted.
Col. Nisbet Balfour, the British commandant of Charlestown, and Lieutenant Col. Lord Rawdon, commander of British forces at Camden and the South Carolina frontier, determined early that Hayne must be executed as an example to the rebels. After a summary trial, the two issued a joint statement sentencing Hayne. When notified of the sentence Hayne sent for Colcock, who argued vigorously for his client.
[Colcock] asked that the ruling be overturned because Hayne had no knowledge of the intent of the board, because no one could be sentenced without a trial except a spy, and because Hayne’s guilt had not been proven. The only reaction to this from the officers in charge was the statement that his sentence was not due to a board of inquiry ruling but by virtue of the authority with which the commander-in-chief in South Carolina and the commanding officer in Charlestown were invested. (4)