During World War II, McCown served in the United States Naval Reserve for two and a half years,[3] where he achieved the rank of lieutenant.
He was stationed in the Pacific Theater as a fighter director/intercept officer aboard an escort carrier,[1] and received six battle stars, the Philippine Liberation Medal, and a Navy Unit Citation.
[1] On December 16, 1964, Governor Frank B. Morrison appointed McCown, under the newly adopted merit-based judicial selection plan, to a seat on the Nebraska Supreme Court vacated by the retirement of Justice Frederick Messmore.
He gained a reputation for his independence and commitment to justice, famously dissenting in a case involving a controversial tax bill signed by the governor who had appointed him.
[1] After retiring from the court, McCown remained active in the legal community, serving as an emeritus member of the American Law Institute's council until 2000.