John was the only son of a lower middle-class family. His father, John Speshock, was a truck driver. His mother, Mildred, was a homemaker and an occasional waitress. He grew up near Paterson, New Jersey, but left at age 16 to attend the Professional Children's School. In 1963, he landed a recurring role on The Patty Duke Show. After that ended, he attended Fairleigh Dickenson University and later New York University, but dropped out to return to acting. John had been an acknowledged alcoholic, who remained sober ever since getting therapy. He had quit smoking in 1999, which he described as "hell on earth". He passed away of a heart attack on December 16, 2005. He will be missed.


January 2000 - John lived with his long-time girl friend, actress-choreographer Patricia Mariano. As a child, he won several 4H awards for the tomatoes he grew. He was an avid gardener. He also collected art & antiques, and was involved in both the New York and L.A. AIDSWalk, which benefits local clinics and AIDS patients. Received excellent stage reviews and a Drama League Award for his vivid reincarnation of the late Dan White, the assassin of San Francisco Mayor George Moscone and Councilman Harvey Milk, in "Execution of Justice" in 1986. Earlier, he won an Obie Award for his portrayal of a returning Vietnam vet in the off-Broadway play "Still Life" in 1981. Art sadly imitated life for John in the end. His "The West Wing" (1999) TV character, Chief of Staff Leo McGarry, had a history of alcoholism and suffered a heart attack. John, who was himself a recovered alcoholic (since 1989), died of a heart attack four days before his 59th birthday in December of 2005. He never married or had children.