The verdict by Superior Court Judge Jean Leonard means Joseph Hall, who was 10 when he shot his father to death at point-blank range in May of 2011, could be sentenced to a juvenile facility until he is 23. He faces a hearing on February 15 to determine where he will be placed.

Jeffrey Hall, 32, was a regional director of the National Socialist Movement, a white separatist group. The case in Riverside, about 100km east of Los Angeles, has made headlines because of his neo-Nazi ties and the rarity of a parent being killed by a child so young.

Leonard said she weighed evidence that the boy had suffered a lifetime of abuse. "He was abused and neglected from the womb," she said. "The NSM taught him things a minor should not know about."

She said at the time of the shooting Joseph Hall understood that what he was doing was wrong.