Butch DeFeo died in 2021. Before he died, he debunked the Lutz's story, saying in a letter to a reporter, "There are no devils, the devil is me." He never did say why he did it.
https://pix11.com/news/local-news/long-island/i-am-the-demon-a-look-at-letters-amityville-horror-killer-ronald-defeo-sent-to-pix11s-marvin-scott/
https://pix11.com/news/local-news/long-island/i-am-the-demon-a-look-at-letters-amityville-horror-killer-ronald-defeo-sent-to-pix11s-marvin-scott/
Butch DeFeo died in 2021. Before he died, he debunked the Lutz's story, saying in a letter to a reporter, "There are no devils, the devil is me." He never did say why he did it.
https://pix11.com/news/local-news/long-island/i-am-the-demon-a-look-at-letters-amityville-horror-killer-ronald-defeo-sent-to-pix11s-marvin-scott/