Subsequent to his graduation from Harvard College he read law in the office of John Williams of Boston, then a leading practitioner in Massachusetts.

When Colonel John Lawrence resigned his position as Judge Advocate General of the Army at the close of the War of Independence, no successor was immediately found for him.

On October 2, 1782, Congress elected Lieutenant Thomas Edwards, then of the 9th Massachusetts Infantry, as Judge Advocate General of the Army, with the rank of colonel.

According to a history of the role published by the Office of the Judge Advocate General, Edwards "gained notoriety in 1783 as a victim of the accepted and rather unsubtle command influence of the day".

This tiny force was expanded somewhat in succeeding years but no successor to Colonel Edwards wag appointed prior to the adoption of the Constitution of the United States.