Born in Milwaukee, Wisconsin, Reilly went to Marquette Academy (now Marquette University High School).
Reilly served in the United States Army during World War II and was on the Allied War Crime Commission.
Reilly served in the Wisconsin State Assembly from 1951 until December 31, 1953, when Governor Walter Kohler Jr. appointed Reilly Judge of Milwaukee County Civil Court.
Reilly died of lung cancer at the Wood Veterans Administration Hospital.
This article about a Republican Party member of the Wisconsin State Assembly born in the 1900s is a stub.