He received a Juris Doctor from University of Iowa College of Law in 1935.

He was in private practice of law in Jefferson, Iowa from 1935 to 1955.

[1] Hanson was nominated by President John F. Kennedy on June 23, 1962, to the United States District Court for the Northern District of Iowa and the United States District Court for the Southern District of Iowa, to a new joint seat created by 75 Stat.

He served as Chief Judge of the Southern District from 1971 to 1977.

His service was terminated on June 6, 1995, due to his death.