He attended high school and junior college at the New Mexico Military Institute.

[3] During World War II, Frank served in the United States Army.

He moved to Santa Fe, New Mexico in 1951 to serve as assistant to the Attorney General before entering private law practice with his father and brother, Dean, the following year.

He resigned in June 1960[3] after being appointed as a judge of the New Mexico Eleventh Judicial District Court by then-Governor John Burroughs.

After his wife's death, Zinn relocated to Michigan to be closer to his son, daughter-in-law, and grandchildren.