From there, the two sides are likely to differ on both the events that preceded the shooting and Joseph's exact motive, elements complicated by his age and the fact that his father, Jeff Hall, was a rabid neo-Nazi. And those facts raise several more philosophical quandaries that, depending on how the judge weighs the answers, may determine the outcome of the trial. Among them: whether virulent racism can amount to parental abuse, whether a child exposed to such hate can understand the difference between right and wrong, and whether someone who grows up in such toxic circumstances can be blamed for wanting a way out.
The prosecutor, Michael Soccio, says that the actions of Joseph Hall have little to do with Nazism, but rather with his anger at being punished and spanked by his father at a party the day before the killing and the boy's worries that his father would leave his family. Though he says he sympathizes with Joseph and his upbringing - "There's a sweet side to him," Mr. Soccio said in an interview this month - he also has little doubt that the boy is a killer.
"What he did, had it been done by anybody older, there would be no doubt that it was a murder," said Mr. Soccio, the chief deputy district attorney in Riverside County. "It's planned. It's premeditated. It was carried out in a cold, killing fashion. It is a murder."
But Joseph's public defender, Matthew J. Hardy, says his client has neurological and psychological problems, compounded by exposure to neo-Nazi "conditioning" and physical abuse in the home.
"He's been conditioned to violence," Mr. Hardy said, adding, "You have to ask yourself: Did this kid really know that this act was wrong based on all those things?"
Instead, Mr. Hardy said, Joseph thought he was being a hero by shooting his father. "He thought what he was doing was right," said Mr. Hardy. "And while that may be hard for other people to understand, in his mind, in a child's mind, if he thought it was right, or at least didn't think it was wrong, then he cannot be held responsible."
Whether that holds true is up to Judge Jean Leonard of Riverside County Superior Court, who will oversee the murder trial without a jury. What is certain, however, is that if found responsible for the killing and made a ward of the state, Joseph, who is now 12, would be the youngest person held in one of the three fenced-in facilities run by California's Department of Juvenile Justice, which houses about 900 of some of the state's most serious juvenile offenders. The median age of these offenders held by the state is 19, and, if found reasonable for the murder, Joseph would likely be held until he was 23.
Joseph Hall's case is also unusual because such acts of violence by children are exceedingly rare. Kathleen M. Heide, a professor of criminology at the University of South Florida, conducted a study and found only 16 arrests of a child under the age of 11 in the killing a parent between 1976 and 2007, roughly one every two years.
Trials in such murders are even rarer, said Robert Weisberg, a co-director of the Stanford Criminal Justice Center, saying he could not recall seeing anyone that young on trial for such a crime in California.
Children as young as 10, or younger, who are accused of murder present special challenges to courts, said Dr. Heide, because of the longstanding legal belief that children are incapable of formulating the intent to commit the crime and do not understand the magnitude of its consequences. Children that young often do not grasp "that death means forever gone," she said.
California's penal code also says that children under 14 cannot be charged with a crime without clear proof that "they knew its wrongfulness."
But Mr. Soccio said that Joseph had a history of violence, including an attack that involved wrapping a telephone cord around a teacher's neck, and needed to be in a security setting "receiving as much help as possible for as long as possible."
"I've had some people say, 'How can you do that to a little kid?' " said Mr. Soccio. "And I ask them, 'Well, would you like him to come live with you?' "
Whatever strategy the lawyers use, life inside the Hall household will most likely come up in the trial, and Joseph may take the stand, Mr. Soccio said. The court could also see testimony from members of the neo-Nazi group the National Socialist Movement, of which Mr. Hall was a West Coast leader.
The day before the killing, Mr. Hall, 32, held a meeting for his members at his suburban Riverside home, where a Nazi flag was hung in the living room. A New York Times reporter, reporting an article about the National Socialist Movement, was also at that meeting, where the group discussed plans for armed patrols on the Mexican border.
At the meeting's start, Mr. Hall, an unemployed plumber who had bragged in the past about teaching his son to shoot a weapon, scolded one of his children for interrupting him - "Get outside or go upstairs and play!" - before telling the group about Joseph's breaking a set of cabinets in the house.
"It was like the twin towers, 9/11, one stack came down, the other stack," he said.
During the meeting, Joseph listened quietly at a table, and later sat with his stepmother, Krista McCary, as she fed a newborn. Mr. Hall had five children, including two from a previous marriage - he was awarded custody of Joseph, the oldest of the five children, and his younger sister after a legal battle with his ex-wife.
The custody battle included allegations of abuse on both sides. Mr. Soccio said that Mr. Hall had occasionally gone "over the top" with physical punishments of Joseph, including kicks to the buttocks. But, he said, "nothing near criminal or even prohibited." Some friends, he said, said "he was a good parent."
But there is also the question of whether Mr. Hall's rhetoric, which included "sieg heils," and neo-Nazi get-togethers in the home amounted to psychological abuse. Mr. Hardy said Joseph had endured episodes of domestic violence and child abuse "as well as the atmosphere that's created by the neo-Nazi activities."
After the meeting, where, Mr. Soccio said, Joseph was spanked for misbehaving, Mr. Hall went out. Mr. Soccio said Joseph might have told a sibling that night that he planned to shoot his father, and Mr. Hardy said another member of the family might have encouraged it.
Just after 4 am, the Riverside police received a 911 from Ms. McCary, reporting that her husband had been shot. Paramedics declared him dead when they arrived. A police report said officers had found a .357 Magnum revolver under Joseph's bed, and an empty holster on a lower shelf in his parents' closet.
In August 2011, Ms. McCary pleaded guilty to child endangerment and criminal storage of a firearm. She and her three biological children now live with Mr. Hall's mother, Mr. Soccio said. Neither woman could be reached for comment.
Joseph is living at a juvenile hall in Riverside, going to school on the grounds of the facility, and is eligible for family visits on weekends and counseling.
And although "tiny" when he arrived in custody, the boy has grown taller and heavier, and would continue to present "a custodial problem wherever he is," Mr. Soccio said. "He's going to be a big man."
Mr. Soccio said that Joseph worried that his father was cheating on his stepmother and that "his family might be falling apart." But Mr. Soccio said he remained skeptical that Mr. Hall's Nazism had much to do with the murder. Rather, he thinks back to something he said the boy had told investigators in the hours after the killing.
"Joseph said at one point," Mr. Soccio recalled, " 'This father and son thing had to come to an end.' "