He served in the United States Army during World War II from 1942 to 1945, where he participated in the Invasion of Normandy.

[1] On March 25, 1971, Barrett was nominated by President Richard Nixon to a seat on the United States Court of Appeals for the Tenth Circuit vacated by Judge Joe Hickey.

He served as a Judge of the United States Foreign Intelligence Surveillance Court of Review from May 19, 1979, to May 18, 1984.

Barrett had a reputation as a staunch conservative and dissented when the Court found that an Oklahoma law banning teachers from publicly supporting gay rights was unconstitutional.

Barret called homosexual conduct “unnatural and detestable” and said that advocacy of it was less deserving of Constitutional protection than “advocacy of violence, sabotage, and terrorism.”[3] He assumed senior status on April 8, 1987, serving in that status until his death.