at their Westfield, New Jersey, home using his own Steyr 9mm handgun and a Colt .22 revolver stolen from his father.
While his children were at school, he shot his wife Helen, 46, in the back of the head, and then his mother Alma, 84, above the left eye. When his daughter Patricia, 16, and son Frederick, 13, arrived home from school, List shot them in the back of the head. After making himself lunch (supposedly a cold cut sandwich), List drove to his bank to close both his and his mother's bank accounts, and then to Westfield High School to watch his oldest son John Frederick, 15, play in a soccer game. After driving John Frederick home, List shot him repeatedly because, as misfire evidence showed, his son attempted to defend himself.
List placed the bodies on sleeping bags in the mansion's ballroom. He left his mother's body in her apartment in the attic. In a long five page letter to his pastor, found on the desk in his study, List claimed he saw too much evil in the world, and had killed his family to save their souls. He then cleaned the various crime scenes, removed his picture from all family photographs in the house, tuned a radio to a religious station, and departed.
For about a month, nobody realized that List had killed his family and fled. The murders were discovered on Dec 7, due to a combination of the family's reclusive tendencies, and to notes sent by List to the children's schools and part-time jobs claiming that the children would be visiting their ailing maternal grandmother in North Carolina for a few weeks.
Helen's mother was in fact ill, and had canceled a visit to Westfield because of it. If she had made the trip she would have been his sixth victim. List also stopped milk, mail, and newspaper deliveries. Neighbors noticed all of the mansion's rooms were illuminated, with no activity in the house. As light bulbs began burning out, they called the police. Officers entered through an unlocked window leading to the basement where they discovered the bodies.
He was on the run for 18 years and was arrested in 1989. He died in prison in 2008.