A 26-year-old man will be tried as an adult on charges he helped his mother torture and murder his two sisters nearly a decade ago.
Placer County Superior Court Judge J. Richard Couzens said this week that William Robert Knorr of North Highlands could not be tried in Juvenile Hall because of his age and the magnitude of the crimes.Knorr, his mother Theresa Knorr, 48, and his brother Robert, 25, are charged with killing half-sisters Suesan Marline Knorr, 17, and Sheila Gay Sanders, 20, in 1984 and 1985.
William Knorr will be arraigned on April 25.
The slayings were not connected until a younger sister, Theresa Marie Groves, 23, talked to Utah authorities last October.
Robert Knorr is serving a prison term in Nevada for an unrelated homicide.
A 12-page probation report filed Feb. 28 says the mother "was an extremely controlling and domineering person."
William's school attendance was poor because his mother kept him home when he had bruises or injuries, the probation officer found.
And although he quit high school after his mother kicked him out of the house with no personal belongings at age 17, William later received his high school diploma through an adult education program.
Bad dreams about his childhood haunt him to this day, the probation officer reported, and he "continues to be very fearful of his mother."
William Knorr admitted to detectives that he lit the match that set Suesan Knorr on fire in 1984, but according to the probation report, "his mother ordered him to light the fire and, if he did not, she would use the remaining gasoline to set him on fire."