Newburn was educated in public schools in Colorado and Arizona. He attended college at Colorado A & M, University of Arizona and the University of Southern California. He graduated from USC in 1950 with a BA Degree and entered the U.S. Navy in November of that year. He was released from the Navy in 1954 and attended University of Southern California Law School. He graduated with a LLB in 1957 and practiced private law from 1958-1989. In 1973, he became President of the San Diego County Bar Association.