Ronald DeFeo nació el 26 de septiembre de 1951 en Brooklyn, Nueva York, Nueva York, Estados Unidos. Estuvo casado con Nissa Burkhalter, Tracey Defeo y Barbara Puco. Murió el 12 de marzo de 2021 en Albany, Nueva York, EE.UU..
Given six concurrent life terms for the slaying of his parents Ronald DeFeo Sr. (43) and Louise DeFeo (42) and his siblings John (9), Marc (12), Allison (13) and Dawn DeFeo (18) at their residence on 112 Ocean Avenue in Amityville, New York on November 13, 1974, while they slept. These murders were the "basis" for "The Amityville Horror".
