Joe Kernan was born on April 8, 1946, in Chicago, Illinois, and was raised in South Bend, Indiana. He graduated from the University of Notre Dame in 1968, and enlisted in the U.S. Navy to attend Aviation Officer Candidate School on January 23, 1969, beginning his training in May 1969. Kernan was commissioned an Ensign on September 5, 1969, and after completing Naval Flight Officer training, reconnaissance training, and RA-5C Vigilante Replacement Air Group training, he served with RVAH-7 at NAS Albany, Georgia, until deploying to Southeast Asia aboard the aircraft carrier USS Kitty Hawk from February 1972 until he was forced to eject over North Vietnam and was taken as a Prisoner of War on May 7, 1972. After spending 326 days in captivity, LTJG Kernan was released during Operation Homecoming on March 28, 1973. He was briefly hospitalized to recover from his injuries at Bethesda Naval Hospital in Bethesda, Maryland, and then served at NAS Marietta, Georgia, until leaving active duty on December 14, 1974. LT Kernan remained in the Naval Reserve until receiving an honorable discharge on August 8, 1982. Joe served as city controller of South Bend, Indiana, from 1980 to 1984, and Mayor of South Bend from 1987 to 1996, when he was elected Lieutenant Governor of Indiana. He became Governor of Indiana upon the death of Governor Frank O'Bannon on September 13, 2003, and served until January 10, 2005. Joe and his wife Maggie were married from 1974 until his death on July 29, 2020. Joe Kernan is buried at Cedar Grove Cemetery in Notre Dame, Indiana.

His Distinguished Flying Cross Citation reads:

For heroism while participating in aerial flight as reconnaissance attack navigator of an aircraft while attached to Reconnaissance Attack Squadron SEVEN embarked in USS KITTY HAWK (CVA-63). On 6 May 1972, Lieutenant (junior grade) KERNAN, in spite of intense enemy anti-aircraft fire and surface-to-air missile threats, was instrumental in obtaining urgently required target development and bomb damage assessment photography of enemy supply and transportation facilities near Nam Dinh, North Vietnam. Lieutenant (junior grade) KERNAN's imaginative and resourceful mission planning, precise navigation and skillful operation of the reconnaissance system provided outstanding quality photographic imagery of the complete Nam Dinh area, allowing construction of current and detailed intelligence data base. Lieutenant (junior grade) KERNAN's superb airmanship, courage and devotion to duty reflected great credit upon himself and were in keeping with the highest traditions of the United States Naval Service.