[1] Harrison graduated from the University of Virginia with a Bachelor of Arts degree in 1977.
Harrison clerked for Judge Robert Bork of the United States Court of Appeals for the District of Columbia Circuit and worked as an associate at Patton Boggs in Washington, D.C.
He then worked with the United States Department of Justice from 1983 to 1993, serving in numerous capacities, including deputy assistant attorney general in the Office of Legal Counsel from 1990 to 1993.
He is the author of an important article on the Privileges or Immunities Clause.
[3] In 2008, Harrison was on leave to serve as counselor on international law in the Office of the Legal Adviser of the Department of State.