He attended the College of William and Mary in 1798. He studied law and then went into private practice.
His judicial career started when he was appointed as a judge of the general court on February 7, 1809. On February 20, 1834, he was appointed a judge of the Supreme Court of Appeals but died just four years later. Judith Brockenbrough"s initials are scratched on a windowpane in an upstairs bedroom at Mount Vernon.
William Brockenbrough"s home in Richmond, at Fifth and Clay streets, was frequently visited by Chief Justice Marshall and other notable citizens of Richmond.
In 1802-1803 he represented Essex County in the House of Delegates and became a member of the Council of State in May, 1803.