"Such was his control over their minds that he could even send them out into the world and they didn't blow the whistle," said Hallowell. "All they had to do was walk into the police station or even just tell their boss ... about what's going on at home and the jig would have been up."
On March 12, 2004, what began as a routine domestic call -- two distraught mothers barred from seeing their children inside 761 West Hammond Avenue -- quickly escalated.
Two of Wesson's nieces, who had borne his children, were there to take them back.
Raw police audio from the scene captured the voices of the two women screaming at Wesson for their children.
Wesson stood at the door, telling the women that he wouldn't give up the kids "under kidnapping conditions," and calmly told police he would cooperate. Then he disappeared into the house.
Two of the children inside the house, 8-year-old Illabelle and 13-month-old Jeva, belonged to Kiani Wesson, Marcus Wesson's oldest daughter. Kiani Wesson was inside the house that day, and watched as her children, along with her closest sister Lise and six other Wesson kids, were led into a back bedroom. She would never see them again.
No one is exactly sure what happened next. Police claim they heard no gunshots.
Kiani Wesson tearfully told ABC News that she thinks Sebhrenah Wesson, her 25-year-old sister, pulled the trigger and killed her son, sister, nieces and nephews.
"I think that he had her take everybody, and then he took her life," said a tearful Kiani Wesson.
Then Marcus Wesson reappeared at the front door of his house, which was by now surrounded by cops and screaming family members, who had feared the worst when Marcus went inside.
Fresno Police Officer Eloy Escareno arrived on the scene just as Wesson was emerging from the house, hands in the air, his clothes stained with blood.
As Marcus Wesson was arrested and led away, Officer Escareno entered the house and was the first to confirm everyone's fears: nine bodies lay in a tangled pile on the floor: Sebhrenah, 25, Elizabeth "Lise," 17, Illabelle, 8, Jonathan and Aviv, both 7, Ethan, 4, and Marshey, Sedona and Jeva all less than two years old.
Sebhrenah and Lise were the daughters of Marcus Wesson and Elizabeth Wesson. All the other children were kids Wesson fathered either with his daughters or nieces.
"I broke down and started crying," Officer Escareno told ABC News. "I was trying to wipe away the tears ... but the father in me was ... just overwhelmed at that point."
As news of the murder exploded across Fresno, most of the media was focused on the killer in dreadlocks. But local TV reporter, Alysia Sofios, was fascinated by the survivors who were defending their father.
Within days, Sofios arranged a meeting with Fino Wesson in an alley behind a local burger joint. At that point, all he could think about was defending his dad. He was determined to clear his name, even though Marcus Wesson now was facing charges of murder, rape and sexual assault.
Like cult members not yet deprogrammed, his sons were loyal.
But Sofios saw beyond the robotic exteriors and knew the Wessons were hurting. She also knew Elizabeth, Gypsy and Kiani had never been to school and had no money -- so she invited them to share her apartment.
But the decision to harbor the Wesson women was not without consequence. She had crossed an ethical boundary that every reporter knows.